Today's Message Index:
----------------------
1. 01:26 AM - Re: Re: Cam Lobe wear (Gene Smith)
2. 04:42 AM - Re: Re: Cam Lobe wear (Kelly McMullen)
3. 08:33 AM - Re: Re: Cam Lobe wear (Monty Barrett Sr)
4. 11:53 AM - Re: Re: Cam Lobe wear (William Becker)
5. 12:48 PM - Re: Re: Cam Lobe wear (jfs)
6. 04:21 PM - Re: Re: Cam Lobe wear (Noel Loveys)
7. 09:52 PM - Re: Re: Cam Lobe wear (Red Hamilton)
Message 1
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| Subject: | Re: Cam Lobe wear |
Kelly.......... Guess there is no end to this...Those so called damaged
engines were all replaced by Mobil...It was a sludge problem so the
operators said...They were all very large engines and commercial operators
in Ca...Mobil was going to fight it, but because of Barrister costs and
dragging it through the courts they decided it was cheaper to settle it by
replacing the engines, and settling down time...They then removed the
aviation oil from the market because they said they weren't making any money
off it, but were just doing it for the convenience of general aviation, so
it was removed...(Now Exxon and Shell are making 50% synthetic, is their
syn. any better than Mobil's?)..Mobil then came out with the 15W50, but for
autos only...I used the Mobil 1 Aviation Oil for years in a C-150 and never
had any sludge problem...The engine went over 2000 hours before each of two
overhauls and the inside of the case and moving parts were golden, not even
black, and obviously no sludge...I now have an RV-4 with a Lycoming
0320(160HP) with 1500 hours using the synthetic as mentioned in the earlier
thread...I popped a cylinder to see what was going on, and inside it was
just as golden as the Cessna...I know because you are an A&P/IA you are
concerned about certified aircraft owners using it...I advocate none of that
at all...Remember, I am EXPERIMENTAL, and operate under different rules.
Questions for you...Does a certified aircraft and engine have to use an
"approved" oil like Exxon and Shell, or can they use any oil of their
choice?..I know break-in oil is straight mineral oil, correct?..Why is this
necessary for break-in?
Enjoyed discussing this with you, and wish you all the luck in the
world...Thanks for all your info and time, you are very knowledgeable, and
informative...........CHEERS!!!!
Gene Smith
RV-4
----- Original Message -----
From: "Kelly McMullen" <apilot2@gmail.com>
Sent: Monday, February 12, 2007 11:28 PM
Subject: Re: Engines-List: Re: Cam Lobe wear
>
> Don't let that Mobil 1 get anywhere near the airport. There was a big
> class action and AD against Mobil 1 aircraft oil, lots of folks didn't
> get the full cost of repairing damage that oil caused to engines,
> props, governors. Exxon Elite or AeroShell 15-50 are both semi
> synthetic. Both around 50-55 a case on sale. Exxon does on-line sale
> for every major aviation event like SnF and OSH and AOPA Expo with
> rebate of some sort to reach that price. They pay shipping(drop
> shipped from closest distributor).
>
> On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
> >
> > Bill B.,
> > I am not familiar with that oil, and did not know it was 50% synthetic,
but
> > thanks for the info, I certainly will investigate the Aeroshell...I get
the
> > Mobil I for $4.00 a quart...Is there a significant difference in price,
not
> > that it makes much difference when you are dealing with an aircraft
engine,
> > you always want the best...I am reluctant to say this, but with all the
> > fraud and lying going on in almost all aspects of our lives now days, I
know
> > for sure I'm getting 50% synthetic when I measure and mix it myself...In
no
> > way am I accusing Shell or any other aspect of aviation of wrong
doing...I
> > run Mobil I in everything I have, including the lawn mower...I have one
auto
> > that the manufacturer requires it...Another reason I use the Aeroshell
in
> > the aircraft mixture is because I'm not sure Mobil I has enough
detergent,
> > otherwise, I would use 100% Mobil I which is 100% synthetic..That is one
> > slick stuff.......Thanks for the info......................CHEERS!!!!
> >
> >
> >
> > ----- Original Message -----
> > From: "William Becker" <wbecker@centurytel.net>
> > To: <engines-list@matronics.com>
> > Sent: Monday, February 12, 2007 9:20 PM
> > Subject: Re: Engines-List: Re: Cam Lobe wear
> >
> >
> > <wbecker@centurytel.net>
> > >
> > > Why not just use Aeroshell 15/50, which is 50% synthetic ? Bill B
> > > ----- Original Message -----
> > > From: "Gene Smith" <esmith6@satx.rr.com>
> > > To: <engines-list@matronics.com>
> > > Sent: Monday, February 12, 2007 6:54 PM
> > > Subject: Re: Engines-List: Re: Cam Lobe wear
> > >
> > >
<esmith6@satx.rr.com>
> > > >
> > > > Kelly,
> > > > You seem like you have experience in this area and are knowledgeable
> > about
> > > > the subject....Educate me about this, if an engine sets up unpickled
for
> > a
> > > > year, I understand from friends of mine that rust forms on the
lobes,
> > and
> > > > when started again, rust flakes off and contaminates the oil system,
> > then
> > > > acts as pumice...Does this rust not show up on a spectrograph
> > sample?..One
> > > > Tripacer owner neglected to change oil very often (if at all) and
> > > > complained
> > > > of the engine not running right...I later saw the camshaft and there
was
> > > > only "nubbins" left...I don't see how the valves functioned at
> > all...I've
> > > > said this before, so will use this opportunity to mention it again,
the
> > > > cheapest thing you can buy for your engine is OIL, and change it
> > often...I
> > > > know the book says change at 50 hours, but I take a good look at
mine at
> > > > 25
> > > > hours and if it exhibits the slightest darkness, then out it
goes...One
> > > > step
> > > > further, I use a 50/50 mix of Aeroshell and Mobil-I 15/w50, and
after
> > 1500
> > > > hours, have had no problems at all...I do not advocate any of you
out
> > > > there
> > > > to use this mixture, especially certified aircraft...It is a
personal
> > > > thing
> > > > with me..........Kelly, thanks for your
inputs...............CHEERS!!!!
> > > >
> > > > Gene Smith
> > > > RV-4
> > > >
> > > >
> > > > ----- Original Message -----
> > > > From: "Kelly McMullen" <apilot2@gmail.com>
> > > > To: <engines-list@matronics.com>
> > > > Sent: Monday, February 12, 2007 3:23 PM
> > > > Subject: Re: Engines-List: Re: Cam Lobe wear
> > > >
> > > >
> > <apilot2@gmail.com>
> > > >>
> > > >> Disagree on the oil analysis. Cam and lifters spall off relatively
> > > >> large chunks of metal, that are not microscopic and never burned in
> > > >> the spectrograph. You may see slightly elevated iron, but nothing
> > > >> startling, but you will see specks of iron in the oil filter. Went
> > > >> through this on my own IO-360 in 2001.
> > > >> KM,
> > > >> A&P/IA
> > > >>
> > > >> On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
> > <esmith6@satx.rr.com>
> > > >> >
> > > >> > Yes, remove a cylinder and use a strong bright light and look up
in
> > > >> > there...I removed #2, and you can see the lobes...The other
choice
> > (and
> > > > the
> > > >> > best) is to buy one of the oil analysis kits (around $10) and
send
> > off
> > > >> > a
> > > >> > sample of your oil, and through a Spectroanalysis system
(S.O.A.P.)
> > > >> > they
> > > > can
> > > >> > tell you which component is wearing excessively by the type and
> > amount
> > > > of
> > > >> > metal in your oil...As you know the different internal parts of
your
> > > > engine
> > > >> > has a different type of metal...i.e: bearings, crankshaft
journals,
> > > > valve
> > > >> > guides, cam lobes and etc.
> > > >> >
> > > >> > Interesting thing here as to the importance of this test, the
USAF
> > > >> > takes
> > > > a
> > > >> > S.O.A.P. sample after each flight of a Jet Fighter, (esp. if it
is
> > > > single
> > > >> > engine) and the aircraft will not be released for the next
mission
> > > >> > until
> > > > the
> > > >> > analysis is complete and deemed safe......................Hope
this
> > > >> > helps...Good luck.............................CHEERS!!!!
> > > >> >
> > > >> > Gene Smith
> > > >> > RV-4
> > > >> >
> > > >> >
> > > >> >
> > > >> > ----- Original Message -----
> > > >> > From: "Gary Casey" <glcasey@adelphia.net>
> > > >> > To: <engines-list@matronics.com>
> > > >> > Sent: Monday, February 12, 2007 7:45 AM
> > > >> > Subject: Engines-List: Re: Cam Lobe wear
> > > >> >
> > > >> >
> > <glcasey@adelphia.net>
> > > >> > >
> > > >> > > Dan,
> > > >> > > Yes, a compression test will not indicate that you have a
problem
> > > >> > > with the cam. If it is really bad a cranking compression
> > > >> > > ("differential" compression test) might show the problem.
Crank
> > the
> > > >> > > engine with the mags and fuel off and note the difference
between
> > > >> > > compression strokes - it is quite easy to tell if one cylinder
is
> > > >> > > really low. You can pull the valve covers and measure the
valve
> > lift
> > > >> > > and that is one way to get a reasonable picture of cam lobe
wear.
> > > >> > > You have to be careful about the hydraulic lifters as if one is
> > > >> > > collapsed you won't get an accurate measurement, but I don't
know
> > how
> > > >> > > to accommodate that, I'm afraid. From what I've heard, by the
time
> > > >> > > the engine is running rough and is low on power the lobe will
be
> > > >> > > essentially wiped off, making this method very effective - and
it
> > > >> > > only takes a few minutes. I've used a simple steel scale, but
a
> > dial
> > > >> > > indicator would be more accurate. However, if you want to get
a
> > real
> > > >> > > look at the cam lobes the only way is to remove a cylinder -
I'm
> > told
> > > >> > > that on a 4-cylinder you can remove just one and get a peak at
all
> > > >> > > the lobes, but I've never tried. Removing a cylinder isn't a
huge
> > > >> > > deal, but it is a pain. It might take a day's labor to get it
> > apart,
> > > >> > > inspected and put all back together. If the engine had no
symptoms
> > > >> > > and looking in the valve covers showed no obvious problem, but
> > showed
> > > >> > > metal in the filter then one has to look inside. With metal in
the
> > > >> > > filter something is going to have to come apart anyway.
> > > >> > >
> > > >> > > Gary Casey
> > > >> > > >
> > > >> > > > Hi Gary,
> > > >> > > >
> > > >> > > > Some long time ago, you wrote the quote below.
> > > >> > > >
> > > >> > > > I am trying to find the cause of rough running in a Lyc
O360A4M
> > > >> > > > that has
> > > >> > > > good compression, good mags, good timing. It has about 1400
smoh
> > > > over
> > > >> > > > about 12 years. There were times during those years in which
it
> > > >> > > > sat for
> > > >> > > > over a year at a time. Also, for most of that time, the oil
> > cooler
> > > >> > > > hoses were connected wrong so the oil ran quite hot.
> > > >> > > >
> > > >> > > > How can I prove that there is or isn't excessive cam lobe
wear
> > > > without
> > > >> > > > tearing it all down??
> > > >> > > >
> > > >> > > > Thanks,
> > > >> > > >
> > > >> > > > Dan
> > > >> > >
> > > >> > >
> > > >> > >
> > > >> > >
> > > >> >
> > > >> >
> > > >> >
> > > >> >
> > > >> >
> > > >> >
> > > >>
> > > >>
> > > >>
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > --
> > > >
> > >
> > >
> > >
> > >
> >
> >
> >
> >
> >
> >
>
>
Message 2
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| Subject: | Re: Cam Lobe wear |
First, the Mobil 1 problem was not isolated to large engines. There
were a lot of private, non-commercial operators. A friend had a
Continental TSIO360 damaged. Mobil fought every claim through
so-called court "masters". A lot of owners suffered uncompensated
losses.
The problem is that synthetic oil does not hold sludge in suspension
the way mineral oil does. That sludge centrifuges out in the worst
places like prop hubs, bottom and top end of the engine, sticking
valves, etc. That is why the approved oils are at least 50% mineral
oil. Whether break-in oil is needed or not is a separate subject.
While you can use what you want in an experimental engine, keep in
mind that a lot of experimentals are flying behind certified engines,
and a lot of evidence supports sticking with approved oils. The
technology for air-cooled aircraft engines hasn't changed in 50 years,
even if you have a few ignition or fuel system improvements. Unless
you are burning true unleaded auto fuel, pure synthetic oil is an
unnecessary risk, in my opinion. The only "aircraft" engine approved
for use of Mobil 1 was the Porsche PFM engine, and it had a lot of
automotive features, since that was its origin. All the other
aircraft use of that oil was by STC approval, which has been revoked.
Certified aircraft must use manufacturer approved oil or STC approved oil.
On 2/13/07, Gene Smith <esmith6@satx.rr.com> wrote:
>
> Kelly.......... Guess there is no end to this...Those so called damaged
> engines were all replaced by Mobil...It was a sludge problem so the
> operators said...They were all very large engines and commercial operators
> in Ca...Mobil was going to fight it, but because of Barrister costs and
> dragging it through the courts they decided it was cheaper to settle it by
> replacing the engines, and settling down time...They then removed the
> aviation oil from the market because they said they weren't making any money
> off it, but were just doing it for the convenience of general aviation, so
> it was removed...(Now Exxon and Shell are making 50% synthetic, is their
> syn. any better than Mobil's?)..Mobil then came out with the 15W50, but for
> autos only...I used the Mobil 1 Aviation Oil for years in a C-150 and never
> had any sludge problem...The engine went over 2000 hours before each of two
> overhauls and the inside of the case and moving parts were golden, not even
> black, and obviously no sludge...I now have an RV-4 with a Lycoming
> 0320(160HP) with 1500 hours using the synthetic as mentioned in the earlier
> thread...I popped a cylinder to see what was going on, and inside it was
> just as golden as the Cessna...I know because you are an A&P/IA you are
> concerned about certified aircraft owners using it...I advocate none of that
> at all...Remember, I am EXPERIMENTAL, and operate under different rules.
>
> Questions for you...Does a certified aircraft and engine have to use an
> "approved" oil like Exxon and Shell, or can they use any oil of their
> choice?..I know break-in oil is straight mineral oil, correct?..Why is this
> necessary for break-in?
>
> Enjoyed discussing this with you, and wish you all the luck in the
> world...Thanks for all your info and time, you are very knowledgeable, and
> informative...........CHEERS!!!!
>
> Gene Smith
> RV-4
>
>
> ----- Original Message -----
> From: "Kelly McMullen" <apilot2@gmail.com>
> To: <engines-list@matronics.com>
> Sent: Monday, February 12, 2007 11:28 PM
> Subject: Re: Engines-List: Re: Cam Lobe wear
>
>
> >
> > Don't let that Mobil 1 get anywhere near the airport. There was a big
> > class action and AD against Mobil 1 aircraft oil, lots of folks didn't
> > get the full cost of repairing damage that oil caused to engines,
> > props, governors. Exxon Elite or AeroShell 15-50 are both semi
> > synthetic. Both around 50-55 a case on sale. Exxon does on-line sale
> > for every major aviation event like SnF and OSH and AOPA Expo with
> > rebate of some sort to reach that price. They pay shipping(drop
> > shipped from closest distributor).
> >
> > On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
> > >
> > > Bill B.,
> > > I am not familiar with that oil, and did not know it was 50% synthetic,
> but
> > > thanks for the info, I certainly will investigate the Aeroshell...I get
> the
> > > Mobil I for $4.00 a quart...Is there a significant difference in price,
> not
> > > that it makes much difference when you are dealing with an aircraft
> engine,
> > > you always want the best...I am reluctant to say this, but with all the
> > > fraud and lying going on in almost all aspects of our lives now days, I
> know
> > > for sure I'm getting 50% synthetic when I measure and mix it myself...In
> no
> > > way am I accusing Shell or any other aspect of aviation of wrong
> doing...I
> > > run Mobil I in everything I have, including the lawn mower...I have one
> auto
> > > that the manufacturer requires it...Another reason I use the Aeroshell
> in
> > > the aircraft mixture is because I'm not sure Mobil I has enough
> detergent,
> > > otherwise, I would use 100% Mobil I which is 100% synthetic..That is one
> > > slick stuff.......Thanks for the info......................CHEERS!!!!
> > >
> > >
> > >
> > > ----- Original Message -----
> > > From: "William Becker" <wbecker@centurytel.net>
> > > To: <engines-list@matronics.com>
> > > Sent: Monday, February 12, 2007 9:20 PM
> > > Subject: Re: Engines-List: Re: Cam Lobe wear
> > >
> > >
> > > <wbecker@centurytel.net>
> > > >
> > > > Why not just use Aeroshell 15/50, which is 50% synthetic ? Bill B
> > > > ----- Original Message -----
> > > > From: "Gene Smith" <esmith6@satx.rr.com>
> > > > To: <engines-list@matronics.com>
> > > > Sent: Monday, February 12, 2007 6:54 PM
> > > > Subject: Re: Engines-List: Re: Cam Lobe wear
> > > >
> > > >
> <esmith6@satx.rr.com>
> > > > >
> > > > > Kelly,
> > > > > You seem like you have experience in this area and are knowledgeable
> > > about
> > > > > the subject....Educate me about this, if an engine sets up unpickled
> for
> > > a
> > > > > year, I understand from friends of mine that rust forms on the
> lobes,
> > > and
> > > > > when started again, rust flakes off and contaminates the oil system,
> > > then
> > > > > acts as pumice...Does this rust not show up on a spectrograph
> > > sample?..One
> > > > > Tripacer owner neglected to change oil very often (if at all) and
> > > > > complained
> > > > > of the engine not running right...I later saw the camshaft and there
> was
> > > > > only "nubbins" left...I don't see how the valves functioned at
> > > all...I've
> > > > > said this before, so will use this opportunity to mention it again,
> the
> > > > > cheapest thing you can buy for your engine is OIL, and change it
> > > often...I
> > > > > know the book says change at 50 hours, but I take a good look at
> mine at
> > > > > 25
> > > > > hours and if it exhibits the slightest darkness, then out it
> goes...One
> > > > > step
> > > > > further, I use a 50/50 mix of Aeroshell and Mobil-I 15/w50, and
> after
> > > 1500
> > > > > hours, have had no problems at all...I do not advocate any of you
> out
> > > > > there
> > > > > to use this mixture, especially certified aircraft...It is a
> personal
> > > > > thing
> > > > > with me..........Kelly, thanks for your
> inputs...............CHEERS!!!!
> > > > >
> > > > > Gene Smith
> > > > > RV-4
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > From: "Kelly McMullen" <apilot2@gmail.com>
> > > > > To: <engines-list@matronics.com>
> > > > > Sent: Monday, February 12, 2007 3:23 PM
> > > > > Subject: Re: Engines-List: Re: Cam Lobe wear
> > > > >
> > > > >
> > > <apilot2@gmail.com>
> > > > >>
> > > > >> Disagree on the oil analysis. Cam and lifters spall off relatively
> > > > >> large chunks of metal, that are not microscopic and never burned in
> > > > >> the spectrograph. You may see slightly elevated iron, but nothing
> > > > >> startling, but you will see specks of iron in the oil filter. Went
> > > > >> through this on my own IO-360 in 2001.
> > > > >> KM,
> > > > >> A&P/IA
> > > > >>
> > > > >> On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
> > > <esmith6@satx.rr.com>
> > > > >> >
> > > > >> > Yes, remove a cylinder and use a strong bright light and look up
> in
> > > > >> > there...I removed #2, and you can see the lobes...The other
> choice
> > > (and
> > > > > the
> > > > >> > best) is to buy one of the oil analysis kits (around $10) and
> send
> > > off
> > > > >> > a
> > > > >> > sample of your oil, and through a Spectroanalysis system
> (S.O.A.P.)
> > > > >> > they
> > > > > can
> > > > >> > tell you which component is wearing excessively by the type and
> > > amount
> > > > > of
> > > > >> > metal in your oil...As you know the different internal parts of
> your
> > > > > engine
> > > > >> > has a different type of metal...i.e: bearings, crankshaft
> journals,
> > > > > valve
> > > > >> > guides, cam lobes and etc.
> > > > >> >
> > > > >> > Interesting thing here as to the importance of this test, the
> USAF
> > > > >> > takes
> > > > > a
> > > > >> > S.O.A.P. sample after each flight of a Jet Fighter, (esp. if it
> is
> > > > > single
> > > > >> > engine) and the aircraft will not be released for the next
> mission
> > > > >> > until
> > > > > the
> > > > >> > analysis is complete and deemed safe......................Hope
> this
> > > > >> > helps...Good luck.............................CHEERS!!!!
> > > > >> >
> > > > >> > Gene Smith
> > > > >> > RV-4
> > > > >> >
> > > > >> >
> > > > >> >
> > > > >> > ----- Original Message -----
> > > > >> > From: "Gary Casey" <glcasey@adelphia.net>
> > > > >> > To: <engines-list@matronics.com>
> > > > >> > Sent: Monday, February 12, 2007 7:45 AM
> > > > >> > Subject: Engines-List: Re: Cam Lobe wear
> > > > >> >
> > > > >> >
> > > <glcasey@adelphia.net>
> > > > >> > >
> > > > >> > > Dan,
> > > > >> > > Yes, a compression test will not indicate that you have a
> problem
> > > > >> > > with the cam. If it is really bad a cranking compression
> > > > >> > > ("differential" compression test) might show the problem.
> Crank
> > > the
> > > > >> > > engine with the mags and fuel off and note the difference
> between
> > > > >> > > compression strokes - it is quite easy to tell if one cylinder
> is
> > > > >> > > really low. You can pull the valve covers and measure the
> valve
> > > lift
> > > > >> > > and that is one way to get a reasonable picture of cam lobe
> wear.
> > > > >> > > You have to be careful about the hydraulic lifters as if one is
> > > > >> > > collapsed you won't get an accurate measurement, but I don't
> know
> > > how
> > > > >> > > to accommodate that, I'm afraid. From what I've heard, by the
> time
> > > > >> > > the engine is running rough and is low on power the lobe will
> be
> > > > >> > > essentially wiped off, making this method very effective - and
> it
> > > > >> > > only takes a few minutes. I've used a simple steel scale, but
> a
> > > dial
> > > > >> > > indicator would be more accurate. However, if you want to get
> a
> > > real
> > > > >> > > look at the cam lobes the only way is to remove a cylinder -
> I'm
> > > told
> > > > >> > > that on a 4-cylinder you can remove just one and get a peak at
> all
> > > > >> > > the lobes, but I've never tried. Removing a cylinder isn't a
> huge
> > > > >> > > deal, but it is a pain. It might take a day's labor to get it
> > > apart,
> > > > >> > > inspected and put all back together. If the engine had no
> symptoms
> > > > >> > > and looking in the valve covers showed no obvious problem, but
> > > showed
> > > > >> > > metal in the filter then one has to look inside. With metal in
> the
> > > > >> > > filter something is going to have to come apart anyway.
> > > > >> > >
> > > > >> > > Gary Casey
> > > > >> > > >
> > > > >> > > > Hi Gary,
> > > > >> > > >
> > > > >> > > > Some long time ago, you wrote the quote below.
> > > > >> > > >
> > > > >> > > > I am trying to find the cause of rough running in a Lyc
> O360A4M
> > > > >> > > > that has
> > > > >> > > > good compression, good mags, good timing. It has about 1400
> smoh
> > > > > over
> > > > >> > > > about 12 years. There were times during those years in which
> it
> > > > >> > > > sat for
> > > > >> > > > over a year at a time. Also, for most of that time, the oil
> > > cooler
> > > > >> > > > hoses were connected wrong so the oil ran quite hot.
> > > > >> > > >
> > > > >> > > > How can I prove that there is or isn't excessive cam lobe
> wear
> > > > > without
> > > > >> > > > tearing it all down??
> > > > >> > > >
> > > > >> > > > Thanks,
> > > > >> > > >
> > > > >> > > > Dan
> > > > >> > >
> > > > >> > >
> > > > >> > >
> > > > >> > >
> > > > >> >
> > > > >> >
> > > > >> >
> > > > >> >
> > > > >> >
> > > > >> >
> > > > >>
> > > > >>
> > > > >>
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
>
>
Message 3
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| Subject: | Re: Cam Lobe wear |
Sorry, Guys. Camshafts in Lycomings anc Continentals are NOT nitrided.
The Lycoming is AISI 8620 and is carborized, about .030 deep.
Don't know what the material is in TCM but it looks like and acts like a
1080 forging in which case it has enough carbon to harden without
carborizing.
Monty Barrett
BPE, Inc.
-----Original Message-----
From: owner-engines-list-server@matronics.com
[mailto:owner-engines-list-server@matronics.com] On Behalf Of Kelly
McMullen
Sent: Monday, February 12, 2007 7:47 PM
Subject: Re: Engines-List: Re: Cam Lobe wear
What happens is a bit of rust or imperfection in the nitride layer
causes a breakthrough to softer metal, on either cam or follower or
both. Once that happens metal comes off quickly in relatively large
particles..ones you can see. Oil analysis only detects metals at the
microscopic size, that are vaporized in the spectrograph. Larger
particles don't make it from the bottom of the sump, typically. My cam
disintegrated, and luckily I was cutting the filter and saw the metal,
and had to pull the oil pump for the AD on that and found it badly
scored from the metal, so it was tear down time. I kept the cam and
lifters as examples. I got to buy a replacement crank, new cam and
lifters, and a new prop hub out of that episode...not all because of
the cam, but from what I found on teardown. The good part is new prop
hub I bought in 2002 is exempt from the current AD just issued this
year. One gets very intimate with the details when you are building an
engine for a type certified plane that you plan to fly, and may
eventually sell to someone else, who will have your name in the
logbooks as the mechanic that authorized its return to service, and
may sue you 20 years later because it quit on them, even though they
are 8 years and who knows how many hours past TBO.
On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
>
> Kelly,
> You seem like you have experience in this area and are knowledgeable
about
> the subject....Educate me about this, if an engine sets up unpickled
for a
> year, I understand from friends of mine that rust forms on the lobes,
and
> when started again, rust flakes off and contaminates the oil system,
then
> acts as pumice...Does this rust not show up on a spectrograph
sample?..One
> Tripacer owner neglected to change oil very often (if at all) and
complained
> of the engine not running right...I later saw the camshaft and there
was
> only "nubbins" left...I don't see how the valves functioned at
all...I've
> said this before, so will use this opportunity to mention it again,
the
> cheapest thing you can buy for your engine is OIL, and change it
often...I
> know the book says change at 50 hours, but I take a good look at mine
at 25
> hours and if it exhibits the slightest darkness, then out it
goes...One step
> further, I use a 50/50 mix of Aeroshell and Mobil-I 15/w50, and after
1500
> hours, have had no problems at all...I do not advocate any of you out
there
> to use this mixture, especially certified aircraft...It is a personal
thing
> with me..........Kelly, thanks for your
inputs...............CHEERS!!!!
>
> Gene Smith
> RV-4
>
>
> ----- Original Message -----
> From: "Kelly McMullen" <apilot2@gmail.com>
> To: <engines-list@matronics.com>
> Sent: Monday, February 12, 2007 3:23 PM
> Subject: Re: Engines-List: Re: Cam Lobe wear
>
>
<apilot2@gmail.com>
> >
> > Disagree on the oil analysis. Cam and lifters spall off relatively
> > large chunks of metal, that are not microscopic and never burned in
> > the spectrograph. You may see slightly elevated iron, but nothing
> > startling, but you will see specks of iron in the oil filter. Went
> > through this on my own IO-360 in 2001.
> > KM,
> > A&P/IA
> >
> > On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
<esmith6@satx.rr.com>
> > >
> > > Yes, remove a cylinder and use a strong bright light and look up
in
> > > there...I removed #2, and you can see the lobes...The other choice
(and
> the
> > > best) is to buy one of the oil analysis kits (around $10) and send
off a
> > > sample of your oil, and through a Spectroanalysis system
(S.O.A.P.) they
> can
> > > tell you which component is wearing excessively by the type and
amount
> of
> > > metal in your oil...As you know the different internal parts of
your
> engine
> > > has a different type of metal...i.e: bearings, crankshaft
journals,
> valve
> > > guides, cam lobes and etc.
> > >
> > > Interesting thing here as to the importance of this test, the USAF
takes
> a
> > > S.O.A.P. sample after each flight of a Jet Fighter, (esp. if it is
> single
> > > engine) and the aircraft will not be released for the next mission
until
> the
> > > analysis is complete and deemed safe......................Hope
this
> > > helps...Good luck.............................CHEERS!!!!
> > >
> > > Gene Smith
> > > RV-4
> > >
> > >
> > >
> > > ----- Original Message -----
> > > From: "Gary Casey" <glcasey@adelphia.net>
> > > To: <engines-list@matronics.com>
> > > Sent: Monday, February 12, 2007 7:45 AM
> > > Subject: Engines-List: Re: Cam Lobe wear
> > >
> > >
<glcasey@adelphia.net>
> > > >
> > > > Dan,
> > > > Yes, a compression test will not indicate that you have a
problem
> > > > with the cam. If it is really bad a cranking compression
> > > > ("differential" compression test) might show the problem. Crank
the
> > > > engine with the mags and fuel off and note the difference
between
> > > > compression strokes - it is quite easy to tell if one cylinder
is
> > > > really low. You can pull the valve covers and measure the valve
lift
> > > > and that is one way to get a reasonable picture of cam lobe
wear.
> > > > You have to be careful about the hydraulic lifters as if one is
> > > > collapsed you won't get an accurate measurement, but I don't
know how
> > > > to accommodate that, I'm afraid. From what I've heard, by the
time
> > > > the engine is running rough and is low on power the lobe will be
> > > > essentially wiped off, making this method very effective - and
it
> > > > only takes a few minutes. I've used a simple steel scale, but a
dial
> > > > indicator would be more accurate. However, if you want to get a
real
> > > > look at the cam lobes the only way is to remove a cylinder - I'm
told
> > > > that on a 4-cylinder you can remove just one and get a peak at
all
> > > > the lobes, but I've never tried. Removing a cylinder isn't a
huge
> > > > deal, but it is a pain. It might take a day's labor to get it
apart,
> > > > inspected and put all back together. If the engine had no
symptoms
> > > > and looking in the valve covers showed no obvious problem, but
showed
> > > > metal in the filter then one has to look inside. With metal in
the
> > > > filter something is going to have to come apart anyway.
> > > >
> > > > Gary Casey
> > > > >
> > > > > Hi Gary,
> > > > >
> > > > > Some long time ago, you wrote the quote below.
> > > > >
> > > > > I am trying to find the cause of rough running in a Lyc
O360A4M
> > > > > that has
> > > > > good compression, good mags, good timing. It has about 1400
smoh
> over
> > > > > about 12 years. There were times during those years in which
it
> > > > > sat for
> > > > > over a year at a time. Also, for most of that time, the oil
cooler
> > > > > hoses were connected wrong so the oil ran quite hot.
> > > > >
> > > > > How can I prove that there is or isn't excessive cam lobe wear
> without
> > > > > tearing it all down??
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Dan
> > > >
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
>
>
Message 4
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| Subject: | Re: Cam Lobe wear |
Gene,
I'm no oil expert by any means, but I read a column by Ben Visser in
General Aviation News www.generalaviationnews.com , he is an oil and fuel
expert. Ben says that automotive oils use detergents and aviation oils use
ashless dispersants. Both are for keeping the engine clean, but the
detergents can cause carbon in aircraft engines, which could cause
preignition. Might be a reason not to use an automotive oil, even a great
one like Mobile 1 in aircraft. You can email Ben, maybe he could give his
opinion,
visser@GeneralAviationNews.com
By the way I used the aircraft Mobile 1 for years in a banner tow aircraft,
and it went past TBO, never had a cylinder off. Now I use AeroShell 15/50
semisynthetic
Bill Becker.
----- Original Message -----
From: "Gene Smith" <esmith6@satx.rr.com>
Sent: Monday, February 12, 2007 10:50 PM
Subject: Re: Engines-List: Re: Cam Lobe wear
>
> Bill B.,
> I am not familiar with that oil, and did not know it was 50% synthetic,
> but
> thanks for the info, I certainly will investigate the Aeroshell...I get
> the
> Mobil I for $4.00 a quart...Is there a significant difference in price,
> not
> that it makes much difference when you are dealing with an aircraft
> engine,
> you always want the best...I am reluctant to say this, but with all the
> fraud and lying going on in almost all aspects of our lives now days, I
> know
> for sure I'm getting 50% synthetic when I measure and mix it myself...In
> no
> way am I accusing Shell or any other aspect of aviation of wrong doing...I
> run Mobil I in everything I have, including the lawn mower...I have one
> auto
> that the manufacturer requires it...Another reason I use the Aeroshell in
> the aircraft mixture is because I'm not sure Mobil I has enough detergent,
> otherwise, I would use 100% Mobil I which is 100% synthetic..That is one
> slick stuff.......Thanks for the info......................CHEERS!!!!
>
>
> ----- Original Message -----
> From: "William Becker" <wbecker@centurytel.net>
> To: <engines-list@matronics.com>
> Sent: Monday, February 12, 2007 9:20 PM
> Subject: Re: Engines-List: Re: Cam Lobe wear
>
>
> <wbecker@centurytel.net>
>>
>> Why not just use Aeroshell 15/50, which is 50% synthetic ? Bill B
>> ----- Original Message -----
>> From: "Gene Smith" <esmith6@satx.rr.com>
>> To: <engines-list@matronics.com>
>> Sent: Monday, February 12, 2007 6:54 PM
>> Subject: Re: Engines-List: Re: Cam Lobe wear
>>
>>
>> >
>> > Kelly,
>> > You seem like you have experience in this area and are knowledgeable
> about
>> > the subject....Educate me about this, if an engine sets up unpickled
>> > for
> a
>> > year, I understand from friends of mine that rust forms on the lobes,
> and
>> > when started again, rust flakes off and contaminates the oil system,
> then
>> > acts as pumice...Does this rust not show up on a spectrograph
> sample?..One
>> > Tripacer owner neglected to change oil very often (if at all) and
>> > complained
>> > of the engine not running right...I later saw the camshaft and there
>> > was
>> > only "nubbins" left...I don't see how the valves functioned at
> all...I've
>> > said this before, so will use this opportunity to mention it again, the
>> > cheapest thing you can buy for your engine is OIL, and change it
> often...I
>> > know the book says change at 50 hours, but I take a good look at mine
>> > at
>> > 25
>> > hours and if it exhibits the slightest darkness, then out it goes...One
>> > step
>> > further, I use a 50/50 mix of Aeroshell and Mobil-I 15/w50, and after
> 1500
>> > hours, have had no problems at all...I do not advocate any of you out
>> > there
>> > to use this mixture, especially certified aircraft...It is a personal
>> > thing
>> > with me..........Kelly, thanks for your inputs...............CHEERS!!!!
>> >
>> > Gene Smith
>> > RV-4
>> >
>> >
>> > ----- Original Message -----
>> > From: "Kelly McMullen" <apilot2@gmail.com>
>> > To: <engines-list@matronics.com>
>> > Sent: Monday, February 12, 2007 3:23 PM
>> > Subject: Re: Engines-List: Re: Cam Lobe wear
>> >
>> >
> <apilot2@gmail.com>
>> >>
>> >> Disagree on the oil analysis. Cam and lifters spall off relatively
>> >> large chunks of metal, that are not microscopic and never burned in
>> >> the spectrograph. You may see slightly elevated iron, but nothing
>> >> startling, but you will see specks of iron in the oil filter. Went
>> >> through this on my own IO-360 in 2001.
>> >> KM,
>> >> A&P/IA
>> >>
>> >> On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
> <esmith6@satx.rr.com>
>> >> >
>> >> > Yes, remove a cylinder and use a strong bright light and look up in
>> >> > there...I removed #2, and you can see the lobes...The other choice
> (and
>> > the
>> >> > best) is to buy one of the oil analysis kits (around $10) and send
> off
>> >> > a
>> >> > sample of your oil, and through a Spectroanalysis system (S.O.A.P.)
>> >> > they
>> > can
>> >> > tell you which component is wearing excessively by the type and
> amount
>> > of
>> >> > metal in your oil...As you know the different internal parts of your
>> > engine
>> >> > has a different type of metal...i.e: bearings, crankshaft journals,
>> > valve
>> >> > guides, cam lobes and etc.
>> >> >
>> >> > Interesting thing here as to the importance of this test, the USAF
>> >> > takes
>> > a
>> >> > S.O.A.P. sample after each flight of a Jet Fighter, (esp. if it is
>> > single
>> >> > engine) and the aircraft will not be released for the next mission
>> >> > until
>> > the
>> >> > analysis is complete and deemed safe......................Hope this
>> >> > helps...Good luck.............................CHEERS!!!!
>> >> >
>> >> > Gene Smith
>> >> > RV-4
>> >> >
>> >> >
>> >> >
>> >> > ----- Original Message -----
>> >> > From: "Gary Casey" <glcasey@adelphia.net>
>> >> > To: <engines-list@matronics.com>
>> >> > Sent: Monday, February 12, 2007 7:45 AM
>> >> > Subject: Engines-List: Re: Cam Lobe wear
>> >> >
>> >> >
> <glcasey@adelphia.net>
>> >> > >
>> >> > > Dan,
>> >> > > Yes, a compression test will not indicate that you have a problem
>> >> > > with the cam. If it is really bad a cranking compression
>> >> > > ("differential" compression test) might show the problem. Crank
> the
>> >> > > engine with the mags and fuel off and note the difference between
>> >> > > compression strokes - it is quite easy to tell if one cylinder is
>> >> > > really low. You can pull the valve covers and measure the valve
> lift
>> >> > > and that is one way to get a reasonable picture of cam lobe wear.
>> >> > > You have to be careful about the hydraulic lifters as if one is
>> >> > > collapsed you won't get an accurate measurement, but I don't know
> how
>> >> > > to accommodate that, I'm afraid. From what I've heard, by the
>> >> > > time
>> >> > > the engine is running rough and is low on power the lobe will be
>> >> > > essentially wiped off, making this method very effective - and it
>> >> > > only takes a few minutes. I've used a simple steel scale, but a
> dial
>> >> > > indicator would be more accurate. However, if you want to get a
> real
>> >> > > look at the cam lobes the only way is to remove a cylinder - I'm
> told
>> >> > > that on a 4-cylinder you can remove just one and get a peak at all
>> >> > > the lobes, but I've never tried. Removing a cylinder isn't a huge
>> >> > > deal, but it is a pain. It might take a day's labor to get it
> apart,
>> >> > > inspected and put all back together. If the engine had no
>> >> > > symptoms
>> >> > > and looking in the valve covers showed no obvious problem, but
> showed
>> >> > > metal in the filter then one has to look inside. With metal in
>> >> > > the
>> >> > > filter something is going to have to come apart anyway.
>> >> > >
>> >> > > Gary Casey
>> >> > > >
>> >> > > > Hi Gary,
>> >> > > >
>> >> > > > Some long time ago, you wrote the quote below.
>> >> > > >
>> >> > > > I am trying to find the cause of rough running in a Lyc O360A4M
>> >> > > > that has
>> >> > > > good compression, good mags, good timing. It has about 1400
>> >> > > > smoh
>> > over
>> >> > > > about 12 years. There were times during those years in which it
>> >> > > > sat for
>> >> > > > over a year at a time. Also, for most of that time, the oil
> cooler
>> >> > > > hoses were connected wrong so the oil ran quite hot.
>> >> > > >
>> >> > > > How can I prove that there is or isn't excessive cam lobe wear
>> > without
>> >> > > > tearing it all down??
>> >> > > >
>> >> > > > Thanks,
>> >> > > >
>> >> > > > Dan
>> >> > >
>> >> > >
>> >> > >
>> >> > >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >>
>> >>
>> >>
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> > --
>> >
>>
>>
>>
>>
>
>
> --
>
Message 5
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| Subject: | Re: Cam Lobe wear |
I asked my lil' brother for his take on this thread. His response follows:
"Some of these guys are really misguided on many things, and some of them
appear to be playing alchemist by mixing on their own volition. This is a
strict no-no for many reasons. No time this morning for a full response,
but a few points:
Mobil 1 is an automotive oil, not approved for any Lyc or Continental
as every other automotive oil is not... they contain detergents which
can foul spark plugs in aircraft engines, particularly. the bottom plug.
This is why only ashless oils are recommended, like Exxon Elite or the
Aeroshell M/G. There is only one exception I can think of where Mobil 1
is used, in fact the only oil recommended... the Mooney Porsche, which
the Germans at Porsche recommended only 1 oil for... 2 different
viscosities of M1 depending on the ambient temp. I have heard of folks
using M1 or someone else's auto oil in a Lycoming or Continental... all
I can say is that they are fools and in violation of the OEM's, all of
whom recommend only aviation oils. Aircraft engines are run under
relatively slow speed, steady speed conditions for hours at a time...
perfect conditions for deposits to form on spark plugs, Using detergent
auto oils is therefore a safety of flight issue, and therefore the
reason only ashless dispersant oils are approved.
There is no better wear protection oil in the marketplace than Mobil
1... one of the reasons it is used by so many NASCAR teams and in F1,
IRL, LeMans and so many other race classes. ExxonMobil has run it a
million miles in a BMW under severe conditions... miniscule wear and an
engine that was super clean at test end.
The Mobil 1 that the writer below is probably referring to was Mobil AV
1, not Mobil 1. It was removed from the market many years ago, but the
press and some of the trade rags got it way overblown w/ mistruths. It
worked wonderfully in Lycomings and most Continentals, but when flown
infrequently in certain big bore Continentals, there were a few ring
sticking incidents. This can occur with all oils when moisture and
infrequent flying get together, esp at altitude where some of the high
flyers have to operate at richer mixtures to keep things cool. Avgas
has a lot of lead, and the extra lead at rich mixture settings, and
moisture get together to form a lead paste. This is the stuff that can
stick ring/s or accumulate in props (which are when you think of it,
perfect centrifuges)
I saw a ton of engines flown to TBO that operated on Mobil AV1... that
thing got real political and emotional. Mobil ended up paying bogus
claims... we saw falsified logbooks etc... it was ugly, what some pilots
will do to get $$$ out of any big pocket supplier. I hate lawyers and
anybody related to one.
There are still a number of pilots using Mobil AV1 with great
satisfaction, altho' it was removed from the market many years ago (some
loaded up on supply near the end) Believe me, when flown under the
right conditions, you can't believe how clean those engines were. Go
into the Smithsonian Air & Space Museum sometime, look up at the Voyager
and notice the Mobil AV 1 decal... that around the world, non-stop
flight used only Mobil AV1. Again, a good oil that got a bad rap...
The reason ExxonMobil and Shell use partial synthetics (again, ashless)
for their premium offerings is that the mineral oil portion has good
natural "solvency" for keeping unwanted material in fine suspension, to
be later drained out during the oil change. The synthetic portion gives
the low temp performance and the high temp thermal and oxidative
stability plus great wear protection... the additives used are key in
enhancing the performance, especially w.r.t. wear & anti-rust
performance
One last comment about the guy who mixes... don't, especially an
automotive with an aircraft oil. Your friends seem to have no idea what
an oil like Exxon Elite has to go through... for starters, a series of
lab tests... if successful (reviewed by the SAE Technical Committee 8
(chaired by the USN)), then a 150 hour endurance test (a real engine (we
ran a Lyc TIO-540J2BD, a Piper Chieftain powerplant), run in a test cell
under a variety of climb. descent and cruise profiles). If you get
through that , you go to a 500 hour flight eval in 2 different engines.
We chose the 2 most difficult, higher temp T/C engines... the Lyc
previously mentioned & for the Continental, the TSIO520-BCE (used in a
Cessna 402). All engines are disassembled and pre-measured for wear,
then flown (both in test cell and on wing), then disassembled again and
inspected/post measured for wear... all oil wetted parts... cams, valve
guides, crank, cylinders, pistons, bearings etc... The engines are also
sludge & deposit rated, so that in addition to wear performance, the oil
needs to demonstrate excellent cleanliness. This rigor of approval is
exactly why ExxonMobil's, Shell's, Phillip's etc stance on using
additives of any kind is the way it is... one simply can't test all the
possible combinations of "mouse milk" additives out there. It is
usually wasted money spent. Stick to a great oil like Elite and be done
with it. We look at a ton of cams that have been flown to TBO, and with
Elite especially they look good with very minimal wear. The key is to
fly as regular as possible, and use an oil with the highest level of
rust protection available... these are most always the multi-grades, and
among those, the Elite really stands out (we designed it that way, as
statistics show that the average pilot in the US flies less than ~50
hours per year. We have a lot of data to back up this claim, both rust
and wear protection is unsurpassed with Elite. You don't need to pass
this along, as in re-reading it sounds like a commercial, but it's my
life, and as an Engineer, I've seen too much data and too many engines.
Can I go to work now?"
----- Original Message -----
From: "Kelly McMullen" <apilot2@gmail.com>
Sent: Monday, February 12, 2007 10:28 PM
Subject: Re: Engines-List: Re: Cam Lobe wear
>
> Don't let that Mobil 1 get anywhere near the airport. There was a big
> class action and AD against Mobil 1 aircraft oil, lots of folks didn't
> get the full cost of repairing damage that oil caused to engines,
> props, governors. Exxon Elite or AeroShell 15-50 are both semi
> synthetic. Both around 50-55 a case on sale. Exxon does on-line sale
> for every major aviation event like SnF and OSH and AOPA Expo with
> rebate of some sort to reach that price. They pay shipping(drop
> shipped from closest distributor).
>
> On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
...
..
.
JF Schaefer, Sr.
Message 6
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| Subject: | Re: Cam Lobe wear |
I know one guy who drops a bit of Aeroshell semi synthetic into his car a
couple of hundred miles before an oil change. He swears it cleans out any
sludge in his engine.
Noel
> -----Original Message-----
> From: owner-engines-list-server@matronics.com
> [mailto:owner-engines-list-server@matronics.com] On Behalf Of
> William Becker
> Sent: Tuesday, February 13, 2007 4:23 PM
> To: engines-list@matronics.com
> Subject: Re: Engines-List: Re: Cam Lobe wear
>
>
> <wbecker@centurytel.net>
>
> Gene,
> I'm no oil expert by any means, but I read a column by
> Ben Visser in
> General Aviation News www.generalaviationnews.com , he is an
> oil and fuel
> expert. Ben says that automotive oils use detergents and
> aviation oils use
> ashless dispersants. Both are for keeping the engine clean, but the
> detergents can cause carbon in aircraft engines, which could cause
> preignition. Might be a reason not to use an automotive oil,
> even a great
> one like Mobile 1 in aircraft. You can email Ben, maybe he
> could give his
> opinion,
> visser@GeneralAviationNews.com
> By the way I used the aircraft Mobile 1 for years in a banner
> tow aircraft,
> and it went past TBO, never had a cylinder off. Now I use
> AeroShell 15/50
> semisynthetic
> Bill Becker.
>
> ----- Original Message -----
> From: "Gene Smith" <esmith6@satx.rr.com>
> To: <engines-list@matronics.com>
> Sent: Monday, February 12, 2007 10:50 PM
> Subject: Re: Engines-List: Re: Cam Lobe wear
>
>
> <esmith6@satx.rr.com>
> >
> > Bill B.,
> > I am not familiar with that oil, and did not know it was
> 50% synthetic,
> > but
> > thanks for the info, I certainly will investigate the
> Aeroshell...I get
> > the
> > Mobil I for $4.00 a quart...Is there a significant
> difference in price,
> > not
> > that it makes much difference when you are dealing with an aircraft
> > engine,
> > you always want the best...I am reluctant to say this, but
> with all the
> > fraud and lying going on in almost all aspects of our lives
> now days, I
> > know
> > for sure I'm getting 50% synthetic when I measure and mix
> it myself...In
> > no
> > way am I accusing Shell or any other aspect of aviation of
> wrong doing...I
> > run Mobil I in everything I have, including the lawn
> mower...I have one
> > auto
> > that the manufacturer requires it...Another reason I use
> the Aeroshell in
> > the aircraft mixture is because I'm not sure Mobil I has
> enough detergent,
> > otherwise, I would use 100% Mobil I which is 100%
> synthetic..That is one
> > slick stuff.......Thanks for the
> info......................CHEERS!!!!
> >
> >
> >
> > ----- Original Message -----
> > From: "William Becker" <wbecker@centurytel.net>
> > To: <engines-list@matronics.com>
> > Sent: Monday, February 12, 2007 9:20 PM
> > Subject: Re: Engines-List: Re: Cam Lobe wear
> >
> >
> > <wbecker@centurytel.net>
> >>
> >> Why not just use Aeroshell 15/50, which is 50% synthetic ?
> Bill B
> >> ----- Original Message -----
> >> From: "Gene Smith" <esmith6@satx.rr.com>
> >> To: <engines-list@matronics.com>
> >> Sent: Monday, February 12, 2007 6:54 PM
> >> Subject: Re: Engines-List: Re: Cam Lobe wear
> >>
> >>
> <esmith6@satx.rr.com>
> >> >
> >> > Kelly,
> >> > You seem like you have experience in this area and are
> knowledgeable
> > about
> >> > the subject....Educate me about this, if an engine sets
> up unpickled
> >> > for
> > a
> >> > year, I understand from friends of mine that rust forms
> on the lobes,
> > and
> >> > when started again, rust flakes off and contaminates the
> oil system,
> > then
> >> > acts as pumice...Does this rust not show up on a spectrograph
> > sample?..One
> >> > Tripacer owner neglected to change oil very often (if at all) and
> >> > complained
> >> > of the engine not running right...I later saw the
> camshaft and there
> >> > was
> >> > only "nubbins" left...I don't see how the valves functioned at
> > all...I've
> >> > said this before, so will use this opportunity to
> mention it again, the
> >> > cheapest thing you can buy for your engine is OIL, and change it
> > often...I
> >> > know the book says change at 50 hours, but I take a good
> look at mine
> >> > at
> >> > 25
> >> > hours and if it exhibits the slightest darkness, then
> out it goes...One
> >> > step
> >> > further, I use a 50/50 mix of Aeroshell and Mobil-I
> 15/w50, and after
> > 1500
> >> > hours, have had no problems at all...I do not advocate
> any of you out
> >> > there
> >> > to use this mixture, especially certified aircraft...It
> is a personal
> >> > thing
> >> > with me..........Kelly, thanks for your
> inputs...............CHEERS!!!!
> >> >
> >> > Gene Smith
> >> > RV-4
> >> >
> >> >
> >> > ----- Original Message -----
> >> > From: "Kelly McMullen" <apilot2@gmail.com>
> >> > To: <engines-list@matronics.com>
> >> > Sent: Monday, February 12, 2007 3:23 PM
> >> > Subject: Re: Engines-List: Re: Cam Lobe wear
> >> >
> >> >
> > <apilot2@gmail.com>
> >> >>
> >> >> Disagree on the oil analysis. Cam and lifters spall off
> relatively
> >> >> large chunks of metal, that are not microscopic and
> never burned in
> >> >> the spectrograph. You may see slightly elevated iron,
> but nothing
> >> >> startling, but you will see specks of iron in the oil
> filter. Went
> >> >> through this on my own IO-360 in 2001.
> >> >> KM,
> >> >> A&P/IA
> >> >>
> >> >> On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
> > <esmith6@satx.rr.com>
> >> >> >
> >> >> > Yes, remove a cylinder and use a strong bright light
> and look up in
> >> >> > there...I removed #2, and you can see the lobes...The
> other choice
> > (and
> >> > the
> >> >> > best) is to buy one of the oil analysis kits (around
> $10) and send
> > off
> >> >> > a
> >> >> > sample of your oil, and through a Spectroanalysis
> system (S.O.A.P.)
> >> >> > they
> >> > can
> >> >> > tell you which component is wearing excessively by
> the type and
> > amount
> >> > of
> >> >> > metal in your oil...As you know the different
> internal parts of your
> >> > engine
> >> >> > has a different type of metal...i.e: bearings,
> crankshaft journals,
> >> > valve
> >> >> > guides, cam lobes and etc.
> >> >> >
> >> >> > Interesting thing here as to the importance of this
> test, the USAF
> >> >> > takes
> >> > a
> >> >> > S.O.A.P. sample after each flight of a Jet Fighter,
> (esp. if it is
> >> > single
> >> >> > engine) and the aircraft will not be released for the
> next mission
> >> >> > until
> >> > the
> >> >> > analysis is complete and deemed
> safe......................Hope this
> >> >> > helps...Good luck.............................CHEERS!!!!
> >> >> >
> >> >> > Gene Smith
> >> >> > RV-4
> >> >> >
> >> >> >
> >> >> >
> >> >> > ----- Original Message -----
> >> >> > From: "Gary Casey" <glcasey@adelphia.net>
> >> >> > To: <engines-list@matronics.com>
> >> >> > Sent: Monday, February 12, 2007 7:45 AM
> >> >> > Subject: Engines-List: Re: Cam Lobe wear
> >> >> >
> >> >> >
> > <glcasey@adelphia.net>
> >> >> > >
> >> >> > > Dan,
> >> >> > > Yes, a compression test will not indicate that you
> have a problem
> >> >> > > with the cam. If it is really bad a cranking compression
> >> >> > > ("differential" compression test) might show the
> problem. Crank
> > the
> >> >> > > engine with the mags and fuel off and note the
> difference between
> >> >> > > compression strokes - it is quite easy to tell if
> one cylinder is
> >> >> > > really low. You can pull the valve covers and
> measure the valve
> > lift
> >> >> > > and that is one way to get a reasonable picture of
> cam lobe wear.
> >> >> > > You have to be careful about the hydraulic lifters
> as if one is
> >> >> > > collapsed you won't get an accurate measurement,
> but I don't know
> > how
> >> >> > > to accommodate that, I'm afraid. From what I've
> heard, by the
> >> >> > > time
> >> >> > > the engine is running rough and is low on power the
> lobe will be
> >> >> > > essentially wiped off, making this method very
> effective - and it
> >> >> > > only takes a few minutes. I've used a simple steel
> scale, but a
> > dial
> >> >> > > indicator would be more accurate. However, if you
> want to get a
> > real
> >> >> > > look at the cam lobes the only way is to remove a
> cylinder - I'm
> > told
> >> >> > > that on a 4-cylinder you can remove just one and
> get a peak at all
> >> >> > > the lobes, but I've never tried. Removing a
> cylinder isn't a huge
> >> >> > > deal, but it is a pain. It might take a day's
> labor to get it
> > apart,
> >> >> > > inspected and put all back together. If the engine had no
> >> >> > > symptoms
> >> >> > > and looking in the valve covers showed no obvious
> problem, but
> > showed
> >> >> > > metal in the filter then one has to look inside.
> With metal in
> >> >> > > the
> >> >> > > filter something is going to have to come apart anyway.
> >> >> > >
> >> >> > > Gary Casey
> >> >> > > >
> >> >> > > > Hi Gary,
> >> >> > > >
> >> >> > > > Some long time ago, you wrote the quote below.
> >> >> > > >
> >> >> > > > I am trying to find the cause of rough running in
> a Lyc O360A4M
> >> >> > > > that has
> >> >> > > > good compression, good mags, good timing. It has
> about 1400
> >> >> > > > smoh
> >> > over
> >> >> > > > about 12 years. There were times during those
> years in which it
> >> >> > > > sat for
> >> >> > > > over a year at a time. Also, for most of that
> time, the oil
> > cooler
> >> >> > > > hoses were connected wrong so the oil ran quite hot.
> >> >> > > >
> >> >> > > > How can I prove that there is or isn't excessive
> cam lobe wear
> >> > without
> >> >> > > > tearing it all down??
> >> >> > > >
> >> >> > > > Thanks,
> >> >> > > >
> >> >> > > > Dan
> >> >> > >
> >> >> > >
> >> >> > >
> >> >> > >
> >> >> >
> >> >> >
> >> >> >
> >> >> >
> >> >> >
> >> >> >
> >> >>
> >> >>
> >> >>
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> > --
> >> >
> >>
> >>
> >>
> >>
> >
> >
> >
> >
> >
> >
> >
> >
> > --
> >
>
>
>
>
>
Message 7
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| Subject: | Re: Cam Lobe wear |
Thanks for the straight scoop Monty.
Red Hamilton
----- Original Message -----
From: Monty Barrett Sr
To: engines-list@matronics.com
Sent: Tuesday, February 13, 2007 8:37 AM
Subject: RE: Engines-List: Re: Cam Lobe wear
<MONTY@BPAENGINES.COM>
Sorry, Guys. Camshafts in Lycomings and Continentals are NOT
nitrided.
The Lycoming is AISI 8620 and is carborized, about .030 deep.
Don't know what the material is in TCM but it looks like and acts like
a
1080 forging in which case it has enough carbon to harden without
carborizing.
Monty Barrett
BPE, Inc.
-----Original Message-----
From: owner-engines-list-server@matronics.com
[mailto:owner-engines-list-server@matronics.com] On Behalf Of Kelly
McMullen
Sent: Monday, February 12, 2007 7:47 PM
To: engines-list@matronics.com
Subject: Re: Engines-List: Re: Cam Lobe wear
<apilot2@gmail.com>
What happens is a bit of rust or imperfection in the nitride layer
causes a breakthrough to softer metal, on either cam or follower or
both. Once that happens metal comes off quickly in relatively large
particles..ones you can see. Oil analysis only detects metals at the
microscopic size, that are vaporized in the spectrograph. Larger
particles don't make it from the bottom of the sump, typically. My cam
disintegrated, and luckily I was cutting the filter and saw the metal,
and had to pull the oil pump for the AD on that and found it badly
scored from the metal, so it was tear down time. I kept the cam and
lifters as examples. I got to buy a replacement crank, new cam and
lifters, and a new prop hub out of that episode...not all because of
the cam, but from what I found on teardown. The good part is new prop
hub I bought in 2002 is exempt from the current AD just issued this
year. One gets very intimate with the details when you are building an
engine for a type certified plane that you plan to fly, and may
eventually sell to someone else, who will have your name in the
logbooks as the mechanic that authorized its return to service, and
may sue you 20 years later because it quit on them, even though they
are 8 years and who knows how many hours past TBO.
On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
<esmith6@satx.rr.com>
>
> Kelly,
> You seem like you have experience in this area and are knowledgeable
about
> the subject....Educate me about this, if an engine sets up unpickled
for a
> year, I understand from friends of mine that rust forms on the
lobes,
and
> when started again, rust flakes off and contaminates the oil system,
then
> acts as pumice...Does this rust not show up on a spectrograph
sample?..One
> Tripacer owner neglected to change oil very often (if at all) and
complained
> of the engine not running right...I later saw the camshaft and there
was
> only "nubbins" left...I don't see how the valves functioned at
all...I've
> said this before, so will use this opportunity to mention it again,
the
> cheapest thing you can buy for your engine is OIL, and change it
often...I
> know the book says change at 50 hours, but I take a good look at
mine
at 25
> hours and if it exhibits the slightest darkness, then out it
goes...One step
> further, I use a 50/50 mix of Aeroshell and Mobil-I 15/w50, and
after
1500
> hours, have had no problems at all...I do not advocate any of you
out
there
> to use this mixture, especially certified aircraft...It is a
personal
thing
> with me..........Kelly, thanks for your
inputs...............CHEERS!!!!
>
> Gene Smith
> RV-4
>
>
> ----- Original Message -----
> From: "Kelly McMullen" <apilot2@gmail.com>
> To: <engines-list@matronics.com>
> Sent: Monday, February 12, 2007 3:23 PM
> Subject: Re: Engines-List: Re: Cam Lobe wear
>
>
<apilot2@gmail.com>
> >
> > Disagree on the oil analysis. Cam and lifters spall off relatively
> > large chunks of metal, that are not microscopic and never burned
in
> > the spectrograph. You may see slightly elevated iron, but nothing
> > startling, but you will see specks of iron in the oil filter. Went
> > through this on my own IO-360 in 2001.
> > KM,
> > A&P/IA
> >
> > On 2/12/07, Gene Smith <esmith6@satx.rr.com> wrote:
<esmith6@satx.rr.com>
> > >
> > > Yes, remove a cylinder and use a strong bright light and look up
in
> > > there...I removed #2, and you can see the lobes...The other
choice
(and
> the
> > > best) is to buy one of the oil analysis kits (around $10) and
send
off a
> > > sample of your oil, and through a Spectroanalysis system
(S.O.A.P.) they
> can
> > > tell you which component is wearing excessively by the type and
amount
> of
> > > metal in your oil...As you know the different internal parts of
your
> engine
> > > has a different type of metal...i.e: bearings, crankshaft
journals,
> valve
> > > guides, cam lobes and etc.
> > >
> > > Interesting thing here as to the importance of this test, the
USAF
takes
> a
> > > S.O.A.P. sample after each flight of a Jet Fighter, (esp. if it
is
> single
> > > engine) and the aircraft will not be released for the next
mission
until
> the
> > > analysis is complete and deemed safe......................Hope
this
> > > helps...Good luck.............................CHEERS!!!!
> > >
> > > Gene Smith
> > > RV-4
> > >
> > >
> > >
> > > ----- Original Message -----
> > > From: "Gary Casey" <glcasey@adelphia.net>
> > > To: <engines-list@matronics.com>
> > > Sent: Monday, February 12, 2007 7:45 AM
> > > Subject: Engines-List: Re: Cam Lobe wear
> > >
> > >
<glcasey@adelphia.net>
> > > >
> > > > Dan,
> > > > Yes, a compression test will not indicate that you have a
problem
> > > > with the cam. If it is really bad a cranking compression
> > > > ("differential" compression test) might show the problem.
Crank
the
> > > > engine with the mags and fuel off and note the difference
between
> > > > compression strokes - it is quite easy to tell if one cylinder
is
> > > > really low. You can pull the valve covers and measure the
valve
lift
> > > > and that is one way to get a reasonable picture of cam lobe
wear.
> > > > You have to be careful about the hydraulic lifters as if one
is
> > > > collapsed you won't get an accurate measurement, but I don't
know how
> > > > to accommodate that, I'm afraid. From what I've heard, by the
time
> > > > the engine is running rough and is low on power the lobe will
be
> > > > essentially wiped off, making this method very effective - and
it
> > > > only takes a few minutes. I've used a simple steel scale, but
a
dial
> > > > indicator would be more accurate. However, if you want to get
a
real
> > > > look at the cam lobes the only way is to remove a cylinder -
I'm
told
> > > > that on a 4-cylinder you can remove just one and get a peak at
all
> > > > the lobes, but I've never tried. Removing a cylinder isn't a
huge
> > > > deal, but it is a pain. It might take a day's labor to get it
apart,
> > > > inspected and put all back together. If the engine had no
symptoms
> > > > and looking in the valve covers showed no obvious problem, but
showed
> > > > metal in the filter then one has to look inside. With metal
in
the
> > > > filter something is going to have to come apart anyway.
> > > >
> > > > Gary Casey
> > > > >
> > > > > Hi Gary,
> > > > >
> > > > > Some long time ago, you wrote the quote below.
> > > > >
> > > > > I am trying to find the cause of rough running in a Lyc
O360A4M
> > > > > that has
> > > > > good compression, good mags, good timing. It has about 1400
smoh
> over
> > > > > about 12 years. There were times during those years in
which
it
> > > > > sat for
> > > > > over a year at a time. Also, for most of that time, the oil
cooler
> > > > > hoses were connected wrong so the oil ran quite hot.
> > > > >
> > > > > How can I prove that there is or isn't excessive cam lobe
wear
> without
> > > > > tearing it all down??
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Dan
> > > >
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
>
>
>
>
>
>
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