Today's Message Index:
----------------------
1. 05:59 AM - Re: Cam Lobe wear (Gary Casey)
2. 07:27 AM - Re: Engines-List Digest: 1 Msgs - 02/11/07 (J. Mcculley)
3. 11:09 AM - Re: Re: Cam Lobe wear (Gene Smith)
4. 11:51 AM - Re: Cam Lobe wear (Dan Rogers)
5. 01:24 PM - Re: Re: Cam Lobe wear (Kelly McMullen)
6. 04:52 PM - Re: Re: Cam Lobe wear (Gene Smith)
7. 05:47 PM - Re: Re: Cam Lobe wear (Kelly McMullen)
8. 07:20 PM - Re: Re: Cam Lobe wear (William Becker)
9. 08:48 PM - Re: Re: Cam Lobe wear (Gene Smith)
10. 09:29 PM - Re: Re: Cam Lobe wear (Kelly McMullen)
Message 1
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| Subject: | Re: Cam Lobe wear |
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: Engines-List Digest: 1 Msgs - 02/11/07 |
Dan,
One easy check you can make is to remove the rocker box covers and make
a comparison check of each valve rocker arm amount of travel(in other
words, the valve stem total travel)as the engine is turned by hand
through at least two full engine revolutions in firing order. If one or
more cam lobes are seriously worn more than others, the associated valve
will not open as fully as it should, compared to those with less or no wear.
Jim
--------------------------------------------------------------------------
Engines-List Digest Server wrote:
> 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
>
>
> Gary Casey wrote:
>
>> Often the first sign of cam wear is a rough
>>engine and inspection will show that the cam lobe is gone. For some
>>time the engine tolerated that much iron and didn't fail.
>>Gary Casey
Message 3
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| Subject: | Re: Cam Lobe wear |
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>
Sent: Monday, February 12, 2007 7:45 AM
Subject: Engines-List: Re: Cam Lobe wear
>
> 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 |
Thanks to Gary, Jim, Aaron,and Gene.
Actually, I already have one cyl off for other reasons and didn't even
think to try and look inside!!! The only real symptom right now casting
a question on the cam is roughness that is not explained by anything
else. We did and oil analysis about 8 hours ago and some metals were
high but not real bad. There has not been any visible metal in the filter.
Thanks again, everybody,
Dan
Dan Rogers wrote:
>
> 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
>
>
>
> Gary Casey wrote:
>> Often the first sign of cam wear is a rough engine and inspection
>> will show that the cam lobe is gone. For some time the engine
>> tolerated that much iron and didn't fail. Gary Casey
>>
>>>
>
>
>
>
>
>
Message 5
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| Subject: | Re: Cam Lobe wear |
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:
>
> 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
>
>
> >
> > 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 6
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| Subject: | 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>
Sent: Monday, February 12, 2007 3:23 PM
Subject: Re: Engines-List: Re: Cam Lobe wear
>
> 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:
> >
> > 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
> >
> >
> > >
> > > 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 |
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
>
>
> >
> > 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:
> > >
> > > 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
> > >
> > >
> > > >
> > > > 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 8
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| Subject: | Re: Cam Lobe wear |
Why not just use Aeroshell 15/50, which is 50% synthetic ? Bill B
----- Original Message -----
From: "Gene Smith" <esmith6@satx.rr.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
>
>
>>
>> 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:
>> >
>> > 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
>> >
>> >
>> > >
>> > > 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 9
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| Subject: | 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>
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 10
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|
| Subject: | 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
> >
> >
> > >
> > > 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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