Today's Message Index:
----------------------
1. 11:43 AM - Re: Re: Why would my Yak 52 m14p lose power? (Yak Pilot)
2. 11:54 AM - Re: Why would my Yak 52 m14p lose power? (Steve Culp)
3. 07:01 PM - Re: Re: Why would my Yak 52 m14p lose power? (A. Dennis Savarese)
4. 08:01 PM - Re: Re: Why would my Yak 52 m14p lose power? (Yak Pilot)
5. 10:59 PM - Re: Re: Why would my Yak 52 m14p lose power? (Jan Mevis)
Message 1
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| Subject: | Re: Why would my Yak 52 m14p lose power? |
I'll take some flames if necessary, but I feel I must point out that this m
od was actually intended for fixing the throttle lag experienced in a lot o
f M-14PF model engines (400HP) and NOT for the M-14P model, which is the st
raight 360 HP engine.- A normal M-14P engine should run perfectly WITHOUT
needing this modification.- =0A=0APoint number two.- Something that ha
s worked normally in the past, and then suddenly starts working abnormally,
or in a way different from in the past is usually happening because someth
ing has changed and not because something needs to be modified.- I think
this problem meets that description.- =0A=0AThis particular engine lost p
ower when throttled back.- It did not stumble and falter when the throttl
e was advanced from idle on the deck.- This does not sound like an accele
rator pump issue.... ice possibly, water in the fuel, low fuel pressure, a
tank venting problem, you name it... lots of possible causes, but I would b
e very hesitant to recommend the accel pump mod on ANY engine for the descr
ibed problem.- =0A=0ARespectfully, =0A=0AMark Bitterlich =0AN50YK.- =0A
=0Ap.s.- Run this by Sergei Boriak, or better yet Vladimir Yastremski...
I think you will find they will agree.- =0A=0A=0A-=0A=0A=0A=0A_________
_______________________=0AFrom: Eddie Moran <eddiemoranii@yahoo.com>=0ATo:
m14pengines-list@matronics.com=0ASent: Saturday, December 20, 2008 11:18:38
AM=0ASubject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose powe
r?=0A=0A=0ADavid, <<We're removing a plug to uncover the jet below it.>>-
Yes, #10 on the diagram is the plug (11mm) that you pull to get to the jet
.=0A=0AThe jet unscrews, comes out, has a little hole in it.- You plug th
at somehow..(weld, JB, etc.).- Then reinsert the jet and reinstall the 11
mm plug.- =0A=0AMy engine ran much better after the mod with no noted lag
in acceleration.=0A=0AEddie=0A=0A=0A=0A--- On Sat, 12/20/08, DAVID STROUD
<dstroud@storm.ca> wrote:=0A=0AFrom: DAVID STROUD <dstroud@storm.ca>=0ASubj
ect: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?=0ATo: m
14pengines-list@matronics.com=0ADate: Saturday, December 20, 2008, 10:32 AM
=0A=0A=0AI'm slightly confused now. We're removing a plug to uncover the je
t below it. Your last sentence says--- 'plug it and reinstall' , do y
ou mean to =0Aremove the jet, plug it ( the jet ) somehow, then reinstall t
he plugged jet and cover it with the first plug? Is this process done on th
e Huosai =0Aengine too ? thanks..=0A-=0ADavid Stroud---- Ottawa,
Canada=0AChristavia C-FDWS=0AFairchild 51 replica=0Aunder- construction C
-FYXV=0A----- Original Message ----- =0AFrom: Eddie Moran =0ATo: m14pengine
s-list@matronics.com =0ASent: Saturday, December 20, 2008 10:02 AM=0ASubjec
t: Fw: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?=0A=0AMark
,- =0A=0AI am not an expert by any means but I agree on the ice theory.
- I also have a picture of the accel plug fix.- I would plug that if yo
u have not already.- The following info came from Dennis a few years ago.
=0A=0A=0A=0ASee attached.- Item #10 is a plug (11 mm I believe) and under
the plug is the acceleration pump jet.- The jet has a slot in it just li
ke a slotted screw.- Use a straight blade screwdriver to remove.- Plug
it and reinstall.=0A=0AThe figure is attached.=0A=0AEddie Moran=0AN320VT
=0AMurphy Moose=0A=0A--- On Thu, 12/18/08, markgreenway <geewhizmark@gmail.
com> wrote:=0A=0AFrom: markgreenway <geewhizmark@gmail.com>=0ASubject: M14P
Engines-List: Why would my Yak 52 m14p lose power?=0ATo: m14pengines-list@m
atronics.com=0ADate: Thursday, December 18, 2008, 9:30 PM=0A=0A=0A--> M14PE
ngines-List message posted by: "markgreenway"=0A<geewhizmark@gmail.com>=0A
=0AHello Guys=0A=0A Any idea why I lost power and had to make a forced l
anding ,because when=0Acrossing midfield for landing, the motor lost power
when I=0A throttled back. It=0Anever totally died and it regained power onc
e on the ground=0A=0A =0A=0A________________________________=0Aby AVG
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
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=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
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Message 2
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| Subject: | Why would my Yak 52 m14p lose power? |
I had a similar experience.
-
Looking at my log book I have about 2000 hours behind- M-14Ps.-- Abou
t 1200 doing acro flying airshows over the last 15 years.- Never had much
problem with them.- My wife did have a failure a few years ago and here
is a link.
-
http://www.avweb.com/news/safety/182990-1.html
http://www.avweb.com/news/newacft/182747-1.html
-
I was talking -with George about this yesterday and he has quite a bit of
experience with these motors also.
-
A while back I was making passes and noticed a drop in RPM during each pass
..-
I would do a 180 and things would clear up without any throttle change and
come around for another high speed pass.
-
I also noticed a vibration and harmonics change.
-
It was pretty cool and humid out that morning and that might have been a co
ntributing factor.
-
But, looking back on this when I finished mowing the hangar I realize it wa
s just the taller grass causing the John Deere to bog down and probably not
carb ice.
-
I know the Kohler is dynamically balanced and may be similar to the M-14P i
n that reguard.- Because of this I always tell my students never to make
drastic power reductions as this may let the mower stall as you will be cau
ght in the deep grass.
-
So what's this got to do the the M-14?- I don't know.- Kinda like the P
S 5 carbs and geared Lycs.- Not much!
-
Listen-to George and people that have actually had experience with this.<
grin>
-
Ben Morfue and Les Crowder figured out the jet problem in about 1990 and mo
st guys have been using it since.
-
It has worked on about 200 odd-M-14Ps I have had experience with the last
18 years.
-
One other thing.- I can't say how many M-14Ps I have seen with the mixtur
e cap still sealed from the factory.- It helps to adjust this after the m
otor has a few hours on it along with the jet mod.- It is that cover that
has safety wire and a lead stamp on it on the right side of the motor.-
Can be adjusted with motor running.
-
Sincerely,
-
Steve Culp
Culp's Specialties
www.culpsspecialties.com
-
--- On Fri, 12/19/08, Monty Barrett Sr <MONTY@bpaengines.com> wrote:
From: Monty Barrett Sr <MONTY@bpaengines.com>
Subject: RE: M14PEngines-List: Why would my Yak 52 m14p lose power?
George Coy is partially correct with his comments regarding throttle operat
ion.- Also, the M14 is a dynamic counterweighted engine and as such it is
good operating practice to never let the propeller =93 drive =93 the engin
e, particularly at high forward airspeed as the counterweight bushings can
become =93 detuned =93 , which means they get
Literally get hammered out of shape.- I don=92t know how susceptible the
M14 is to this phenomenon but a reduction geared Lycoming is extremely sens
itive to it.
-
I think it is a bad assumption to think that the Russian throttle body carb
uretor will not make carb. Ice.- Here are the reasons I think it can.-
There is a pressure drop
Across the carburetor venturi which, under high humidity conditions can cha
nge water vapor to water in droplet form and some temperature reduction tak
es place because of the expansion after the airflow leaves the venturi. -
-Shortly after this event, fuel is metered into the lower pressure area a
nd is evaporated.- Evaporation is endothermic, which means the temperatur
e is lowered.- Now we have liquid water at a reduced temperature and if t
he reduced temperature is 32 dF, presto, carburetor ice.
-
I have heard this same argument regarding the famous Bendix Pressure Carbs.
and I can testify that a PS-5 WILL make carburetor ice under the above con
ditions.
-
My 2 pence
Monty Barrett
-
-
-----Original Message-----
From: owner-m14pengines-list-server@matronics.com [mailto:owner-m14pengines
-list-server@matronics.com] On Behalf Of John Clayton
Sent: Friday, December 19, 2008 1:44 PM
Subject: RE: M14PEngines-List: Why would my Yak 52 m14p lose power?
-
Dennis
-I would get hold of Jim Kimball Enterprises http://www.jimkimballenterpr
ises.com/web/index.php-they have a mod that you can do to the carb. that
will probably take care of your problem.
-
John Clayton
Pitts Model 12 builder
-
09/03/00 MIXTURE CONTROL, ACCELERATOR PUMP MODS, STUMBLE
The mixture is not actually slaved to the throttle.- It is controlled by
a barrometric pressure anneroid.- This system senses the barr. press. and
sets the mixture accordingly.- From 0 to 5000ft. it stays full rich.-
>From 5000ft up it leans out.- There is an accelerator pump curcuit that i
s coupled to the throttle to ad extra fuel when the throttle is rapidly adv
anced.- This accell pump is the cause of the "stumble" that most M-14Ps h
ave when the throttle is pushed up after being at idle or near idle for a w
hile.- This can be adjusted out with a series of different needles etc to
get it right for your condititions and piloting.- However, nobody does t
his and they live with the stumble.- There is a carb mod done here that w
e have done on our Model 12 and a few other M-14Ps around here.- It invol
ves plugging this accell pump passage.- Very simple, and very effective.
- The throttle response on our 12 is fantastic, like a dragster.- KK
-----Original Message-----
From: owner-m14pengines-list-server@matronics.com [mailto:owner-m14pengines
-list-server@matronics.com]On Behalf Of George Coy
Sent: Friday, December 19, 2008 5:53 AM
Subject: RE: M14PEngines-List: Why would my Yak 52 m14p lose power?
Dennis,
--- As you know the M14P engine has a pressure carb. the fuel is inje
cted down stream of the venturii. It is very similar to a throttle body inj
ection system. As fuel is not evaporating in the low pressure area (lower t
emperature area per Boyles law) by the venturi, the pressure carburetor is
almost immune to carb ice. (particularly in Texas)
--- It is much more likely that the engine loaded up at reduced throt
tle. Reading between the lines, the pilot admits he does not have much expe
rience with radial engines.
I always try to teach new guys to use a throttle reduction to zero thrust r
ather than to completely pull the throttle back. If you really need the dyn
amic braking of a idling engine, then at least :CLEAR" the engine by period
ically opening the throttle and clearing out the loaded up spark plugs.
-
George Coy
-
-
From: owner-m14pengines-list-server@matronics.com [mailto:owner-m14pengines
-list-server@matronics.com] On Behalf Of A. Dennis Savarese
Sent: Friday, December 19, 2008 7:37 AM
Subject: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?
Sounds like it could very well be carb ice.- I would remove and inspect A
LL fuel screens/filters including the one at the rear of the carburetor jus
t above the fuel inlet.- It's a 22 mm nut.
Dennis
-
----- Original Message -----
From: markgreenway
Sent: Thursday, December 18, 2008 8:30 PM
Subject: M14PEngines-List: Why would my Yak 52 m14p lose power?
-
om>
Hello Guys
--- Any idea why I lost power and had to make a forced landing ,becau
se when crossing midfield for landing, the motor lost power when I throttle
d back. It never totally died and it regained power once on the ground afte
r a few minutes and then it powered up and ran just fine?
It has some Les Crowder mods on it, and I am not sure if those mods change
the normal operations of the mp14.
--- I would ask Les Crowder if he were still with us. I have been ask
ing around and have had some great advice from some very nice Yak people.
Just not sure if I am safe. I have been flying a Mooney and a V-Tail, this
is so different.
Now I am afraid to fly until I feel like I have found the answer. It remind
s me of a carb ice situation.
Who around the North Texas area would the right person to pay to go through
the motor and check things out for me?
Thanks so much
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=220084#220084
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Message 3
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| Subject: | Re: Why would my Yak 52 m14p lose power? |
Mark,
There are many, many M14P's, 360 HP engines that exhibit the throttle
response hesitation. The problem is not limited to the PF engine only.
The problem of throttle response hesitation can be reduced by changing
the accelerator pump jet down to a smaller diameter. The smallest
accelerator pump jet is .9 mm and I can say from experience, changing to
the .9 mm jet does not totally eliminate the problem on those engines
that exhibit the problem.
I too have plugged many an accelerator pump jet to stop the hesitation
problem on both P and PF engines. My opinion is, the accelerator pump
jet provides additional fuel during WOT which helps to cool the
cylinders (richer mixture). I'm not sure what the long term impact
might be by plugging the accelerator pump jet.
Dennis
----- Original Message -----
From: Yak Pilot
To: m14pengines-list@matronics.com
Sent: Sunday, December 21, 2008 1:42 PM
Subject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose
power?
I'll take some flames if necessary, but I feel I must point out that
this mod was actually intended for fixing the throttle lag experienced
in a lot of M-14PF model engines (400HP) and NOT for the M-14P model,
which is the straight 360 HP engine. A normal M-14P engine should run
perfectly WITHOUT needing this modification.
Point number two. Something that has worked normally in the past, and
then suddenly starts working abnormally, or in a way different from in
the past is usually happening because something has changed and not
because something needs to be modified. I think this problem meets that
description.
This particular engine lost power when throttled back. It did not
stumble and falter when the throttle was advanced from idle on the deck.
This does not sound like an accelerator pump issue.... ice possibly,
water in the fuel, low fuel pressure, a tank venting problem, you name
it... lots of possible causes, but I would be very hesitant to recommend
the accel pump mod on ANY engine for the described problem.
Respectfully,
Mark Bitterlich
N50YK.
p.s. Run this by Sergei Boriak, or better yet Vladimir Yastremski...
I think you will find they will agree.
-------------------------------------------------------------------------
-----
From: Eddie Moran <eddiemoranii@yahoo.com>
To: m14pengines-list@matronics.com
Sent: Saturday, December 20, 2008 11:18:38 AM
Subject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose
power?
David, << We're removing a plug to uncover the jet below it.>>
Yes, #10 on the diagram is the plug (11mm) that you pull to get to the
jet.
The jet unscrews, comes out, has a little hole in it. You plug
that somehow..(weld, JB, etc.). Then reinsert the jet and reinstall the
11mm plug.
My engine ran much better after the mod with no noted lag in
acceleration.
Eddie
--- On Sat, 12/20/08, DAVID STROUD <dstroud@storm.ca> wrote:
From: DAVID STROUD <dstroud@storm.ca>
Subject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p
lose power?
To: m14pengines-list@matronics.com
Date: Saturday, December 20, 2008, 10:32 AM
I'm slightly confused now. We're removing a plug to uncover
the jet below it. Your last sentence says 'plug it and reinstall' ,
do you mean to
remove the jet, plug it ( the jet ) somehow, then reinstall
the plugged jet and cover it with the first plug? Is this process done
on the Huosai
engine too ? thanks..
David Stroud Ottawa, Canada
Christavia C-FDWS
Fairchild 51 replica
under construction C-FYXV
----- Original Message -----
From: Eddie Moran
To: m14pengines-list@matronics.com
Sent: Saturday, December 20, 2008 10:02 AM
Subject: Fw: Re: M14PEngines-List: Why would my Yak 52 m14p
lose power?
Mark,
I am not an expert by any means but I agree on
the ice theory. I also have a picture of the accel plug fix. I would
plug that if you have not already. The following info came from Dennis
a few years ago.
See attached. Item #10 is a plug (11 mm I
believe) and under the plug is the acceleration pump jet. The jet has a
slot in it just like a slotted screw. Use a straight blade screwdriver
to remove. Plug it and reinstall.
The figure is attached.
Eddie Moran
N320VT
Murphy Moose
--- On Thu, 12/18/08, markgreenway
<geewhizmark@gmail.com> wrote:
From: markgreenway <geewhizmark@gmail.com>
Subject: M14PEngines-List: Why would my Yak
52 m14p lose power?
To: m14pengines-list@matronics.com
Date: Thursday, December 18, 2008, 9:30 PM
"markgreenway"<geewhizmark@gmail.com>Hello Guys Any idea why I lost
power and had to make a forced landing ,because whencrossing midfield
for landing, the motor lost power when I throttled back. Itnever totally
died and it regained power once on the ground
------------------------------------------------------------
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Message 4
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| Subject: | Re: Why would my Yak 52 m14p lose power? |
Was not trying to disagree or start an argument with you Dennis .- Just d
id not believe that this cure was applicable to the problem being described
.- Respectfully, I still do not.- =0A=0ARegarding the stumble in thrott
le movement.- I have talked to many people about this pressure carb.- A
lot of people think they have this thing fully figured out and I have some
doubts there since their explanations seem to differ from the mechanics I
have talked to that are Russians themselves and were trained in that countr
y.- I know that my personal understanding is much less than complete to p
ut it mildly.- I do not have the personal first hand experience to back t
his up, but from what I have seen one Russian do, it appears that the "P" m
odel engines that I have seen stumble are usually able to be cured without
plugging the accel pump.- Some cases have required changing air bleed jet
s to values that "by the book" seemed to be rather extreme, but the change
then allowed the accel pump jet to be pretty much- left alone, or operate
d withinn normal ranges but never plugged.- This is problematic in that t
his puts strong suspicion on proper
operation of the diaphragms in that the-engine was possibly over rich in
the transition -range to begin with. -My comment about P vs. PF engine
s was not meant to imply that the problem could not happen with a P model,
but that in every case I have seen it could be cured by exercising the comp
lete range of adjustments possible with this carb, further that while it ma
y have been tried and used successfully with the P model, that according to
my sources, it was originally intended for the PF model where this problem
happens more often.- I am not sure who "invented" this mod.... Seems to
me I was told once... might have been you, George Coy,- I really am not s
ure.- I hope someone chimes in regarding this so that if I am wrong on th
at point,---I can be corrected.-- Given that there is no magic in
how an engine burns fuel, and that there are a lot of P models that run pe
rfectly without the accel jet plugged, it seems to me that an engine that d
oes
not run right has something out of adjustment (or just not working right i
nternally) and does not need a carb design change.- No question that the
mod works on some engines, but to me it is a matter of robbing Peter to pay
Paul.- =0A=0ABottom line, no one around here has a flow bench for these
things that I know of, or has tried to truly tackle over-hauling one and th
en charting the flow curves on this side of the pond, and since the darn th
ings are no longer in production, long term users may eventually switch to
fuel injection anyway.-- =0A=0AWhile New Bern is not a big airport for
Russian engines,-we have had 5 aircraft with P model engines, all of whic
h ran perfectly without stumble, and another 4 with PF models, ALL of which
stumble some worse than others.- =0A=0A=0AI was told that the carb does
have a circuit for WOT mixture enrichment.- I was also informed the opera
tor can pull the throttle back until a very small change in manifold pressu
re is seen in order to save fuel with minimum performance loss.- Both pie
ces of info came from Russian sources directly, if that means anything.-
=0A-=0AMark Bitterlich=0A-=0A=0A=0A________________________________=0A
=0AFrom: A. Dennis Savarese <dsavarese0812@bellsouth.net>=0ATo: m14pengines
-list@matronics.com=0ASent: Sunday, December 21, 2008 7:00:34 PM=0ASubject:
Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?=0A=0AMark,
=0AThere are many, many M14P's, 360 HP engines that exhibit the throttle re
sponse hesitation.- The problem is not limited to the PF engine only.-
The problem of throttle response hesitation can be reduced by-changing th
e accelerator pump jet down to-a smaller diameter.- The smallest accele
rator pump jet is .9-mm and I can say from experience, changing to the .9
mm jet does not totally eliminate the problem on those engines that exhibi
t the problem.=0A-=0AI too have plugged many an accelerator pump jet to s
top the hesitation problem on both P and PF engines.- My opinion is, the
accelerator pump jet provides additional fuel during WOT-which helps-to
cool the cylinders (richer mixture).- I'm not sure what the long term im
pact might be by plugging the accelerator pump jet.=0A-=0ADennis=0A-=0A
----- Original Message ----- =0AFrom: Yak Pilot =0ATo: m14pengines-list@mat
ronics.com =0ASent: Sunday, December 21, 2008 1:42 PM=0ASubject: Re: Re: M1
4PEngines-List: Why would my Yak 52 m14p lose power?=0A=0AI'll take some fl
ames if necessary, but I feel I must point out that this mod was actually i
ntended for fixing the throttle lag experienced in a lot of M-14PF model en
gines (400HP) and NOT for the M-14P model, which is the straight 360 HP eng
ine.- A normal M-14P engine should run perfectly WITHOUT needing this mod
ification.- =0A=0APoint number two.- Something that has worked normally
in the past, and then suddenly starts working abnormally, or in a way diff
erent from in the past is usually happening because something has changed a
nd not because something needs to be modified.- I think this problem meet
s that description.- =0A=0AThis particular engine lost power when throttl
ed back.- It did not stumble and falter when the throttle was advanced fr
om idle on the deck.- This does not sound like an accelerator pump issue.
... ice possibly, water in the fuel, low fuel pressure, a tank venting prob
lem, you name it... lots of possible causes, but I would be very hesitant t
o recommend the accel pump mod on ANY engine for the described problem.-
=0A=0ARespectfully, =0A=0AMark Bitterlich =0AN50YK.- =0A=0Ap.s.- Run th
is by Sergei Boriak, or better yet Vladimir Yastremski... I think you will
find they will agree.- =0A=0A=0A-=0A=0A=0A=0A__________________________
______=0AFrom: Eddie Moran <eddiemoranii@yahoo.com>=0ATo: m14pengines-list@
matronics.com=0ASent: Saturday, December 20, 2008 11:18:38 AM=0ASubject: Re
: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?=0A=0A=0ADavid,
<<We're removing a plug to uncover the jet below it.>>- Yes, #10 on the
diagram is the plug (11mm) that you pull to get to the jet.=0A=0AThe jet un
screws, comes out, has a little hole in it.- You plug that somehow..(weld
, JB, etc.).- Then reinsert the jet and reinstall the 11mm plug.- =0A
=0AMy engine ran much better after the mod with no noted lag in acceleratio
n.=0A=0AEddie=0A=0A=0A=0A--- On Sat, 12/20/08, DAVID STROUD <dstroud@storm.
ca> wrote:=0A=0AFrom: DAVID STROUD <dstroud@storm.ca>=0ASubject: Re: Re: M1
4PEngines-List: Why would my Yak 52 m14p lose power?=0ATo: m14pengines-list
@matronics.com=0ADate: Saturday, December 20, 2008, 10:32 AM=0A=0A=0AI'm sl
ightly confused now. We're removing a plug to uncover the jet below it. You
r last sentence says--- 'plug it and reinstall' , do you mean to =0Ar
emove the jet, plug it ( the jet ) somehow, then reinstall the plugged jet
and cover it with the first plug? Is this process done on the Huosai =0Aeng
ine too ? thanks..=0A-=0ADavid Stroud---- Ottawa, Canada=0AChrist
avia C-FDWS=0AFairchild 51 replica=0Aunder- construction C-FYXV=0A----- O
riginal Message ----- =0AFrom: Eddie Moran =0ATo: m14pengines-list@matronic
s.com =0ASent: Saturday, December 20, 2008 10:02 AM=0ASubject: Fw: Re: M14P
Engines-List: Why would my Yak 52 m14p lose power?=0A=0AMark,- =0A=0AI am
not an expert by any means but I agree on the ice theory.- I also have a
picture of the accel plug fix.- I would plug that if you have not alread
y.- The following info came from Dennis a few years ago.=0A=0A=0A=0ASee a
ttached.- Item #10 is a plug (11 mm I believe) and under the plug is the
acceleration pump jet.- The jet has a slot in it just like a slotted scre
w.- Use a straight blade screwdriver to remove.- Plug it and reinstall.
=0A=0AThe figure is attached.=0A=0AEddie Moran=0AN320VT =0AMurphy Moose=0A
=0A--- On Thu, 12/18/08, markgreenway <geewhizmark@gmail.com> wrote:=0A=0AF
rom: markgreenway <geewhizmark@gmail.com>=0ASubject: M14PEngines-List: Why
would my Yak 52 m14p lose power?=0ATo: m14pengines-list@matronics.com=0ADat
e: Thursday, December 18, 2008, 9:30 PM=0A=0A=0A--> M14PEngines-List messag
e posted by: "markgreenway"=0A<geewhizmark@gmail.com>=0A=0AHello Guys=0A=0A
Any idea why I lost power and had to make a forced landing ,because whe
n=0Acrossing midfield for landing, the motor lost power when I=0A throttled
back. It=0Anever totally died and it regained power once on the ground=0A
=0A =0A=0A________________________________=0A=0A 3D=3D=3D=3D
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| Subject: | Re: Why would my Yak 52 m14p lose power? |
And also all the Russian mechanics that I know of in Europe, would agree ..
Jan Mevis
RA2005K
From: owner-m14pengines-list-server@matronics.com
[mailto:owner-m14pengines-list-server@matronics.com] On Behalf Of Yak Pilot
Sent: zondag 21 december 2008 20:43
Subject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?
I'll take some flames if necessary, but I feel I must point out that this
mod was actually intended for fixing the throttle lag experienced in a lot
of M-14PF model engines (400HP) and NOT for the M-14P model, which is the
straight 360 HP engine. A normal M-14P engine should run perfectly WITHOUT
needing this modification.
Point number two. Something that has worked normally in the past, and then
suddenly starts working abnormally, or in a way different from in the past
is usually happening because something has changed and not because something
needs to be modified. I think this problem meets that description.
This particular engine lost power when throttled back. It did not stumble
and falter when the throttle was advanced from idle on the deck. This does
not sound like an accelerator pump issue.... ice possibly, water in the
fuel, low fuel pressure, a tank venting problem, you name it... lots of
possible causes, but I would be very hesitant to recommend the accel pump
mod on ANY engine for the described problem.
Respectfully,
Mark Bitterlich
N50YK.
p.s. Run this by Sergei Boriak, or better yet Vladimir Yastremski... I
think you will find they will agree.
_____
From: Eddie Moran <eddiemoranii@yahoo.com>
Sent: Saturday, December 20, 2008 11:18:38 AM
Subject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?
David, << We're removing a plug to uncover the jet below it.>> Yes, #10 on
the diagram is the plug (11mm) that you pull to get to the jet.
The jet unscrews, comes out, has a little hole in it. You plug that
somehow..(weld, JB, etc.). Then reinsert the jet and reinstall the 11mm
plug.
My engine ran much better after the mod with no noted lag in acceleration.
Eddie
--- On Sat, 12/20/08, DAVID STROUD <dstroud@storm.ca> wrote:
From: DAVID STROUD <dstroud@storm.ca>
Subject: Re: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?
I'm slightly confused now. We're removing a plug to uncover the jet below
it. Your last sentence says 'plug it and reinstall' , do you mean to
remove the jet, plug it ( the jet ) somehow, then reinstall the plugged jet
and cover it with the first plug? Is this process done on the Huosai
engine too ? thanks..
David Stroud Ottawa, Canada
Christavia C-FDWS
Fairchild 51 replica
under construction C-FYXV
----- Original Message -----
From: Eddie Moran <mailto:eddiemoranii@yahoo.com>
Sent: Saturday, December 20, 2008 10:02 AM
Subject: Fw: Re: M14PEngines-List: Why would my Yak 52 m14p lose power?
Mark,
I am not an expert by any means but I agree on the ice theory. I also have
a picture of the accel plug fix. I would plug that if you have not already.
The following info came from Dennis a few years ago.
See attached. Item #10 is a plug (11 mm I believe) and under the plug is
the acceleration pump jet. The jet has a slot in it just like a slotted
screw. Use a straight blade screwdriver to remove. Plug it and reinstall.
The figure is attached.
Eddie Moran
N320VT
Murphy Moose
--- On Thu, 12/18/08, markgreenway <geewhizmark@gmail.com> wrote:
From: markgreenway <geewhizmark@gmail.com>
Subject: M14PEngines-List: Why would my Yak 52 m14p lose power?
<geewhizmark@gmail.com>
Hello Guys
Any idea why I lost power and had to make a forced landing ,because when
crossing midfield for landing, the motor lost power when I
throttled back. It
never totally died and it regained power once on the ground
_____
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