Today's Message Index:
----------------------
1. 04:42 AM - Re: Re: Prop seal replacement and subsequent vibration (A. Dennis Savarese)
2. 05:11 AM - Re: Prop seal replacement and subsequent vibration (Scooter)
3. 05:15 AM - Re: Re: Prop seal replacement and subsequent vibration (ggg6@att.net)
4. 10:30 AM - Re: No Spartanburg show. (David McGirt)
5. 02:52 PM - Re: Re: Prop seal replacement and subsequent vibration (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E)
6. 04:19 PM - Request for Info (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E)
7. 04:55 PM - Re: Re: Prop seal replacement and subsequent vibration (Tim & Jessie Windsor)
8. 05:25 PM - Re: Re: Prop seal replacement and subsequent vibration (A. Dennis Savarese)
9. 05:31 PM - Re: Re: Prop seal replacement and subsequent vibration (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E)
10. 07:57 PM - Re: Prop seal replacement and subsequent vibration (Scooter)
Message 1
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| Subject: | Re: Prop seal replacement and subsequent vibration |
--> Yak-List message posted by: "A. Dennis Savarese" <dsavarese@elmore.rr.com>
Scooter,
Why don't you try the simple test I mentioned yesterday? Put a wrap of duct
tape on one of the blades about 2" in from the tip and run the engine. If
it improves, you've got the right blade. If it gets worse, remove the tape
on that blade and put a wrap on the other blade and run it. Regardless of
which blade it is, add a wrap at a time until the vibration becomes
acceptable. You can add spray paint to the back side of the blade once you
find out which blade needs additional weight. Somewhat crude, but it works
and it's a very simple test.
Dennis
----- Original Message -----
From: "Scooter" <yakk52@verizon.net>
Sent: Tuesday, September 05, 2006 8:07 PM
Subject: Yak-List: Re: Prop seal replacement and subsequent vibration
> --> Yak-List message posted by: "Scooter" <yakk52@verizon.net>
>
> Thanks for all the suggestions. I think I've checked just about
> everything mentioned. I ran it again today and I can quantify the
> vibration a bit better. It seems to have several resonant frequencies.
> At 44% the instrument panel shakes to a blur. At 50% the pilot shakes
> (and everything blurs). It is substantial.
>
> I am again thinking it must be the prop. I pulled all the plugs, cleaned
> them and did a "finger" check on compression. Seemed fine (nothing stuck
> open).
>
> At this point I'm thinking the next step is to make a jumbo prop wrench,
> take the blades off, clean out the oil, grease, etc. and replace the seals
> while i'm at it.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=59798#59798
>
>
>
Message 2
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| Subject: | Re: Prop seal replacement and subsequent vibration |
--> Yak-List message posted by: "Scooter" <yakk52@verizon.net>
I'll give that a shot. What bothers me is why this happened. I went from zero
vibration to losing-my-fillings vibration. I'm just wondering if i'll find the
answer when i overhaul the hub?
dsavarese(at)elmore.rr.co wrote:
> Scooter,
> Why don't you try the simple test I mentioned yesterday? Put a wrap of duct
> tape on one of the blades about 2" in from the tip and run the engine. If
> it improves, you've got the right blade. If it gets worse, remove the tape
> on that blade and put a wrap on the other blade and run it. Regardless of
> which blade it is, add a wrap at a time until the vibration becomes
> acceptable. You can add spray paint to the back side of the blade once you
> find out which blade needs additional weight. Somewhat crude, but it works
> and it's a very simple test.
> Dennis
>
> ---
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=59896#59896
Message 3
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| Subject: | Re: Prop seal replacement and subsequent vibration |
With the intake drain open or a broken drain tube the Engine will idle at about
36%.. Gary
-------------- Original message from "Roger Kemp" <viperdoc@mindspring.com>: --------------
> --> Yak-List message posted by: "Roger Kemp"
>
> Mark,
> I have left my intake drain open a couple of times. I did notice it
> misssing but not a violent vibration. If that is what Scooter was trying to
> relate.
> Doc
>
>
> > [Original Message]
> > From: Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E
>
> > To:
> > Date: 9/5/2006 3:31:20 PM
> > Subject: RE: Yak-List: Re: Prop seal replacement and subsequent vibration
> >
> > --> Yak-List message posted by: "Bitterlich, Mark G CIV Det Cherry Point,
> MALS-14 64E"
> >
> >
> > Not to disagree with anyone's suggestions (all good), but the first
> > thing I would do would be to either purchase or borrow an Infra Red
> > Temperature gun.... Run the engine for awhile and then go shoot each
> > cylinder and check for close to the same readings on each one. It might
> > be something so simple as a dead cylinder. Compression checks to
> > follow.
> >
> > Or ... Do the following first:
> >
> >
> > Take a REALLY close look at your intake drain system. A lot of these
> > systems were installed with #4 AN fittings and soft aluminum lines.
> > Over time theses things are prone to crack and break, leaving you with a
> > rather large leak in the intake system, which makes the engine run rough
> > just as you have described. The best solution here of course is to use
> > flexible steel braided lines. I've seen this one nail four people so
> > far... Me being one of them of course.
> >
> > Best of luck,
> >
> > Mark Bitterlich
> > N50YK
> >
> >
> >
> >
> >
>
>
>
>
>
>
<html>
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<head></head>
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<DIV></DIV>With the intake drain open or a broken drain tube the Engine will idle
at about 36%.. Gary<BR>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px
solid">-------------- Original message from "Roger Kemp" <viperdoc@mindspring.com>:
-------------- <BR><BR><BR>> --> Yak-List message posted by:
"Roger Kemp" <VIPERDOC@MINDSPRING.COM><BR>> <BR>> Mark, <BR>> I have
left my intake drain open a couple of times. I did notice it <BR>> misssing
but not a violent vibration. If that is what Scooter was trying to <BR>>
relate. <BR>> Doc <BR>> <BR>> <BR>> > [Original Message] <BR>>
> From: Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E <BR>>
<MARK.BITTERLICH@NAVY.MIL><BR>> > To: <YAK-LIST@MATRONICS.COM><BR>> >
Date: 9/5/2006 3:31:20 PM <BR>> > Subject: RE: Yak-List: Re: Prop seal
replacement and subsequent vibration <BR>> > <BR>> > --> Yak-List
message posted by: "Bitterlich, Mark G CIV Det Cherry Point, <BR>> MALS-14
64E" <MARK.BITTERLICH@NAVY.MIL><BR>> > <B
R>>
> <BR>> > Not to disagree with anyone's suggestions (all good), but the
first <BR>> > thing I would do would be to either purchase or borrow
an Infra Red <BR>> > Temperature gun.... Run the engine for awhile and then
go shoot each <BR>> > cylinder and check for close to the same readings
on each one. It might <BR>> > be something so simple as a dead cylinder.
Compression checks to <BR>> > follow. <BR>> > <BR>> > Or
... Do the following first: <BR>> > <BR>> > <BR>> > Take a
REALLY close look at your intake drain system. A lot of these <BR>> > systems
were installed with #4 AN fittings and soft aluminum lines. <BR>> >
Over time theses things are prone to crack and break, leaving you with a <BR>>
> rather large leak in the intake system, which makes the engine run
rough <BR>> > just as you have described. The best solution here of course
is to use <BR>> > flexible steel braided li
nes. I
=====
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Message 4
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| Subject: | No Spartanburg show. |
Hank,
There is a pretty large group of us that will be at Sparta, TN this Friday
and through the weekend , and flying in the Onieda Airshow.. if you are in
the area, look us up. We would be glad to fly with you.
David
_____
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Hank Gibson
Sent: Tuesday, September 05, 2006 10:26 AM
Subject: Re: Yak-List: No Spartanburg show.
Hi,
FNG here. Since Sartanburg is cancelled; Any lead and/or check pilots
willing to meet and fly some FAST training sorties in the SE for myself and
maybe two others weekend of Sep 16th? Pls contact off list.
Hank "Hoot" Gibson
cjpilot710@aol.com wrote:
Troops,
Just called the Spartanburg airport.
_____
Get your email and more, right on the new
<http://us.rd.yahoo.com/evt=42973/*http:/www.yahoo.com/preview> Yahoo.com
Message 5
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| Subject: | Re: Prop seal replacement and subsequent vibration |
Gary, the actual change in idle RPM will vary from engine to engine, and
also with the location of the leak and how big it is, not to mention
who's version of intake drain kit you have. My engine idles at 20%
normally... with the throttle full back. With the intake drain valve
open, the idle is almost exactly the same. With my engine, the
indicators are: more backfiring in flight with the throttle at idle, and
a possible backfire on take-off if the throttle is pushed forward too
fast. All of this changes if you simply adjust the carb one or two
clicks. For example, when it happened to a PF model M-14, and it was
just a cracked tube, the engine was missing in flight at full power and
under full load (in the vertical). Everywhere else it was just fine.
It is an insidious problem, and no two airplanes are likely to be
identical with their particular symptoms.
V/R,
Mark Bitterlich
p.s. And Doc, I agree that the intake drain leak is not likely to give
you a violent vibration. However, it does change the way the engine
"feels" (per se) as you increase RPM. As I have read about this
problem, it seems I did not quite understand just how severe the
vibration was. At first I thought it was barely perceptible, but
definitely THERE. Now I am hearing: VIOLENT VIBRATION. So... sorry, I
misunderstood. I agree with a lot of other peoples recommendations...
especially the one where someone suggested that the oil tube might have
gotten bent. THAT is very likely considering that when the seals were
replaced, the tube would have had to have force applied to it to put
everything back in place again. POOF... problem starts on next engine
start. After all this, my bet is that it HAS to be in the hub. But
hey... nothing wrong with checking that all cylinders are the same temp,
and that there are no induction leaks, and a compression check. If
those all checked good, along with obvious mag checks, then that pretty
much leaves nothing else BUT the hub/prop.
________________________________
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of ggg6@att.net
Sent: Wednesday, September 06, 2006 3:06
Subject: RE: Yak-List: Re: Prop seal replacement and subsequent
vibration
With the intake drain open or a broken drain tube the Engine will idle
at about 36%.. Gary
-------------- Original message from "Roger Kemp"
<viperdoc@mindspring.com>: --------------
> --> Yak-List message posted by: "Roger Kemp"
>
> Mark,
> I have left my intake drain open a couple of times. I did
notice it
> misssing but not a violent vibration. If that is what Scooter
was trying to
> relate.
> Doc
>
>
> > [Original Message]
> > From: Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E
>
> > To:
> > Date: 9/5/2006 3:31:20 PM
> > Subject: RE: Yak-List: Re: Prop seal replacement and
subsequent vibration
> >
> > --> Yak-List message posted by: "Bitterlich, Mark G CIV Det
Cherry Point,
> MALS-14 64E"
> > > >
> > Not to disagree with anyone's suggestions (all good), but
the first
> > thing I would do would be to either purchase or borrow an
Infra Red
> > Temperature gun.... Run the engine for awhile and then go
shoot each
> > cylinder and check for close to the same readings on each
one. It might
> > be something so simple as a dead cylinder. Compression
checks to
> > follow.
> >
> > Or ... Do the following first:
> >
> >
> > Take a REALLY close look at your intake drain system. A lot
of these
> > systems were installed with #4 AN fittings and soft aluminum
lines.
> > Over time theses things are prone to crack and break,
leaving you with a
> > rather large leak in the intake system, which makes the
engine run rough
> > just as you have described. The best solution here of course
is to use
> > flexible steel braided li nes. I ======
Message 6
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| Subject: | Request for Info |
--> Yak-List message posted by: "Bitterlich, Mark G CIV Det Cherry Point, MALS-14
64E" <mark.bitterlich@navy.mil>
I've had an on-going problem that many YAK-52 and 50 owners will run
into themselves if they hang onto their aircraft long enough. This
problem relates to the cowling (both upper and lower halves) and the way
it has a 180 degree circular aluminum tube to which the actual metal of
the cowl is rolled around and then riveted to.
This aluminum tube rests against a metal ring that the engine shutters
attach to, and over time it will simply wear through (from vibration) or
crack, sometimes in not one, but many places. Any cracks in these tubes
should not be ignored, because as they propagate, they will eventually
go all the way around the tube itself causing it to fail. When this
happens, you can expect to see cracks develop in the actual cowling
sheet metal itself since it is now carrying the load. What happens after
that is not pretty.
Cracks in this tubing can happen more quickly and with more extensive
damage if the leather pads that are part of the engine baffling
arrangement are allowed to deteriorate. These pads are essential to
holding the cowl in place and helping to dampen certain vibration.
Needless to say, I have learned all of this the hard way. My YAK-50 has
about 700 hours on it now and it has been flown hard. The worst of my
damage was due to a previous owner removing the engine shutters, but
that is another story.
As these tubes have cracked in my aircraft, I have filled them with 9309
Hysol epoxy. This was a temp. fix at best, but gave me a few years of
grace before the problem eventually came back.
Now I am faced with not only replacing these tubes, but better yet...
redesigning them to prevent this problem from coming back in the future.
I have managed to obtain two "virgin" tubes from Romania with all the
requisite hardware, but instead of using them, I would like to send them
someplace to be used as a "form" in order to have new tubes made of thin
wall stainless steel. The replacement tubes would have to be dead on
perfect (size/shape/arc/thickness, etc) to work.
Does anyone know of any anyone in the country, individual or firm, that
can take these tubes and duplicate them EXACTLY out of another material?
It would be worthwhile for ALL of us to find someone like this and allow
them to make some up for stock. For proof of this, take a hard look at
these tubes that I am talking about in YOUR 50 or 52.
If the folks over in England have already solved this problem (Rob
Kent?) PLEASE let me know.
Best Regards to all,
Mark Bitterlich
N50YK
Message 7
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| Subject: | Re: Prop seal replacement and subsequent vibration |
--> Yak-List message posted by: "Tim & Jessie Windsor" <windsorsedge@ozemail.com.au>
Guys
I have a standard Russian VHF in my 52
That receives but has stopped transmitting.Sounds like carrier wave only,
have tried reracking but still no good
Tim in Oz
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of A. Dennis Savarese
Sent: Wednesday, 6 September 2006 9:41 PM
Subject: Re: Yak-List: Re: Prop seal replacement and subsequent vibration
--> Yak-List message posted by: "A. Dennis Savarese"
<dsavarese@elmore.rr.com>
Scooter,
Why don't you try the simple test I mentioned yesterday? Put a wrap of duct
tape on one of the blades about 2" in from the tip and run the engine. If
it improves, you've got the right blade. If it gets worse, remove the tape
on that blade and put a wrap on the other blade and run it. Regardless of
which blade it is, add a wrap at a time until the vibration becomes
acceptable. You can add spray paint to the back side of the blade once you
find out which blade needs additional weight. Somewhat crude, but it works
and it's a very simple test.
Dennis
----- Original Message -----
From: "Scooter" <yakk52@verizon.net>
Sent: Tuesday, September 05, 2006 8:07 PM
Subject: Yak-List: Re: Prop seal replacement and subsequent vibration
> --> Yak-List message posted by: "Scooter" <yakk52@verizon.net>
>
> Thanks for all the suggestions. I think I've checked just about
> everything mentioned. I ran it again today and I can quantify the
> vibration a bit better. It seems to have several resonant frequencies.
> At 44% the instrument panel shakes to a blur. At 50% the pilot shakes
> (and everything blurs). It is substantial.
>
> I am again thinking it must be the prop. I pulled all the plugs, cleaned
> them and did a "finger" check on compression. Seemed fine (nothing stuck
> open).
>
> At this point I'm thinking the next step is to make a jumbo prop wrench,
> take the blades off, clean out the oil, grease, etc. and replace the seals
> while i'm at it.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=59798#59798
>
>
>
__________ NOD32 1.1742 (20060906) Information __________
This message was checked by NOD32 antivirus system.
http://www.eset.com
Message 8
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| Subject: | Re: Prop seal replacement and subsequent vibration |
--> Yak-List message posted by: "A. Dennis Savarese" <dsavarese@elmore.rr.com>
You can ship your radio back to Termikas in Lithuania and they will repair
and test it. That is the only company I know of that can do it that we are
able to communicate with. http://www.termikas.com/ No idea how much it
will cost. But at least you can ask.
Dennis
----- Original Message -----
From: "Tim & Jessie Windsor" <windsorsedge@ozemail.com.au>
Sent: Wednesday, September 06, 2006 6:55 PM
Subject: RE: Yak-List: Re: Prop seal replacement and subsequent vibration
> --> Yak-List message posted by: "Tim & Jessie Windsor"
> <windsorsedge@ozemail.com.au>
>
> Guys
> I have a standard Russian VHF in my 52
> That receives but has stopped transmitting.Sounds like carrier wave only,
> have tried reracking but still no good
> Tim in Oz
> -----Original Message-----
> From: owner-yak-list-server@matronics.com
> [mailto:owner-yak-list-server@matronics.com] On Behalf Of A. Dennis
> Savarese
> Sent: Wednesday, 6 September 2006 9:41 PM
> To: yak-list@matronics.com
> Subject: Re: Yak-List: Re: Prop seal replacement and subsequent vibration
>
> --> Yak-List message posted by: "A. Dennis Savarese"
> <dsavarese@elmore.rr.com>
>
> Scooter,
> Why don't you try the simple test I mentioned yesterday? Put a wrap of
> duct
>
> tape on one of the blades about 2" in from the tip and run the engine. If
> it improves, you've got the right blade. If it gets worse, remove the
> tape
> on that blade and put a wrap on the other blade and run it. Regardless of
> which blade it is, add a wrap at a time until the vibration becomes
> acceptable. You can add spray paint to the back side of the blade once
> you
> find out which blade needs additional weight. Somewhat crude, but it
> works
> and it's a very simple test.
> Dennis
>
> ----- Original Message -----
> From: "Scooter" <yakk52@verizon.net>
> To: <yak-list@matronics.com>
> Sent: Tuesday, September 05, 2006 8:07 PM
> Subject: Yak-List: Re: Prop seal replacement and subsequent vibration
>
>
>> --> Yak-List message posted by: "Scooter" <yakk52@verizon.net>
>>
>> Thanks for all the suggestions. I think I've checked just about
>> everything mentioned. I ran it again today and I can quantify the
>> vibration a bit better. It seems to have several resonant frequencies.
>> At 44% the instrument panel shakes to a blur. At 50% the pilot shakes
>> (and everything blurs). It is substantial.
>>
>> I am again thinking it must be the prop. I pulled all the plugs, cleaned
>> them and did a "finger" check on compression. Seemed fine (nothing stuck
>> open).
>>
>> At this point I'm thinking the next step is to make a jumbo prop wrench,
>> take the blades off, clean out the oil, grease, etc. and replace the
>> seals
>
>> while i'm at it.
>>
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=59798#59798
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
> __________ NOD32 1.1742 (20060906) Information __________
>
> This message was checked by NOD32 antivirus system.
> http://www.eset.com
>
>
>
Message 9
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| Subject: | Re: Prop seal replacement and subsequent vibration |
--> Yak-List message posted by: "Bitterlich, Mark G CIV Det Cherry Point, MALS-14
64E" <mark.bitterlich@navy.mil>
Here are a couple of questions:
1. When you transmit do you have sidetone? Excuse me, that is a
military term... When you transmit, can you hear your own voice in the
headphones as you transmit? Is your "sidetone" normal or very weak?
2. I am assuming that you listened in on another radio in another
airplane and you heard a carrier with no microphone audio? Yes, no?
3. Try more than one frequency. Make sure you try another frequency
where each knob on the frequency selector has moved. On the receiving
radio, try moving one click to each side of the frequency that is being
transmitted on and see if you hear any audio at all.
4. Lastly... There is an adjustment on the front of the Balken 5 R/T
that adjusts transmit modulation level. You might try cranking that up
a tad and seeing what happens. Actually, there are TWO adjustments on
the front of the radio. One is for the modulation level, and umm...
Darn, I forget what the other one is for! I'll have to check on the
schematics and get back to you.
If all else fails, I have a working Balken 20 for sale. You really need
to look for the Balken 5, which is more than likely what you have. The
Balken 20 is a high power version of the one typically found in the 52,
and it has four times the power. Meaning, it ain't cheap. :-)
Try George Coy and see if he is selling any radios too... He usually has
Balken 5's for around $450 or so.
Best of luck,
Mark Bitterlich
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Tim & Jessie
Windsor
Sent: Wednesday, September 06, 2006 19:55
Subject: RE: Yak-List: Re: Prop seal replacement and subsequent
vibration
--> Yak-List message posted by: "Tim & Jessie Windsor"
--> <windsorsedge@ozemail.com.au>
Guys
I have a standard Russian VHF in my 52
That receives but has stopped transmitting.Sounds like carrier wave
only, have tried reracking but still no good Tim in Oz -----Original
Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of A. Dennis
Savarese
Sent: Wednesday, 6 September 2006 9:41 PM
Subject: Re: Yak-List: Re: Prop seal replacement and subsequent
vibration
--> Yak-List message posted by: "A. Dennis Savarese"
<dsavarese@elmore.rr.com>
Scooter,
Why don't you try the simple test I mentioned yesterday? Put a wrap of
duct
tape on one of the blades about 2" in from the tip and run the engine.
If it improves, you've got the right blade. If it gets worse, remove
the tape on that blade and put a wrap on the other blade and run it.
Regardless of which blade it is, add a wrap at a time until the
vibration becomes acceptable. You can add spray paint to the back side
of the blade once you find out which blade needs additional weight.
Somewhat crude, but it works and it's a very simple test.
Dennis
----- Original Message -----
From: "Scooter" <yakk52@verizon.net>
Sent: Tuesday, September 05, 2006 8:07 PM
Subject: Yak-List: Re: Prop seal replacement and subsequent vibration
> --> Yak-List message posted by: "Scooter" <yakk52@verizon.net>
>
> Thanks for all the suggestions. I think I've checked just about
> everything mentioned. I ran it again today and I can quantify the
> vibration a bit better. It seems to have several resonant
frequencies.
> At 44% the instrument panel shakes to a blur. At 50% the pilot shakes
> (and everything blurs). It is substantial.
>
> I am again thinking it must be the prop. I pulled all the plugs,
cleaned
> them and did a "finger" check on compression. Seemed fine (nothing
stuck
> open).
>
> At this point I'm thinking the next step is to make a jumbo prop
wrench,
> take the blades off, clean out the oil, grease, etc. and replace the
seals
> while i'm at it.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=59798#59798
>
>
>
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| Subject: | Re: Prop seal replacement and subsequent vibration |
--> Yak-List message posted by: "Scooter" <yakk52@verizon.net>
This is sort of interesting. I calculated the resonant frequency of a Yak-52 (assuming
it is much like a big violin string) and came up with the following:
The resonant frequency of a yak:
fn = nv/2L
n = harmonic (1,2,3...)
v = speed of sound (in steel) = 16,000 ft/sec
L = length = 25.42 ft
f1 = 314 hz
f2 = 628 hz (32% rpm)
f3 = 942 hz (49% rpm)
f4 = 1256 hz (65% rpm)
f5 = 1570 hz (80% rpm)
Note: at 50% rpm the engine rpm is 1475.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=60115#60115
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