---------------------------------------------------------- M14PEngines-List Digest Archive --- Total Messages Posted Sun 12/21/08: 5 ---------------------------------------------------------- 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 _____________________________________ Time: 11:43:32 AM PST US From: Yak Pilot 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 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 =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, <>- 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 wrote:=0A=0AFrom: DAVID STROUD =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 wrote:=0A=0AFrom: markgreenway =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=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 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D ________________________________ Message 2 _____________________________________ Time: 11:54:30 AM PST US From: Steve Culp Subject: RE: M14PEngines-List: 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 wrote: From: Monty Barrett Sr 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 http://www.matronics.com/c Thank you for your generous ;----- ---------------- -Matt Dralle, List nbsp; ------ Features Chat, http://www.mnbsp;----- via the Web href="http://forums.matronics.com">http://forums.matronics.com _============= --href="http://www.matronics.com/contribution">http://www.matronics.c om/chref="http://www.matronics.com/Navigator?M14PEngines-List">http://www ..matronics.com/Navigator?M14PEngines-Listhref="http://forums.matronics.co m">http://forums.matronics.com--href="http://www.matronics.com/contri bution">http://www.matronics.com/chref="http://www.matronics.com/Navigato r?M14PEngines-List">http://www.matronics.com/Navigator?M14PEngines-Listhref ="http://forums.matronics.com">http://forums.matronics.com--http://ww w.matronics.com/contributionhttp://www.matronics.com/Navigator?M14PEngines- Listhttp://forums.matronics.com ________________________________ Message 3 _____________________________________ Time: 07:01:17 PM PST US From: "A. Dennis Savarese" Subject: Re: Re: M14PEngines-List: 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 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 wrote: From: DAVID STROUD 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 wrote: From: markgreenway 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"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 ------------------------------------------------------------ 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D ________________________________ Message 4 _____________________________________ Time: 08:01:50 PM PST US From: Yak Pilot Subject: Re: Re: M14PEngines-List: 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 =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 =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, <>- 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 wrote:=0A=0AFrom: DAVID STROUD =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 wrote:=0A=0AF rom: markgreenway =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=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 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D href='3D"ht tp://www.matronics.com/contribution"'>http://www.matronics.com/contribution 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D href='3D"http://www.matronics.com/Navigator?M14PEngines-List"'>htt p://www.matronics.com/Navigator?M14PEngines-List 3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D href='3D"http://for ums.matronics.com"'>http://forums.matronics.com 3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 =============== ________________________________ Message 5 _____________________________________ Time: 10:59:04 PM PST US From: "Jan Mevis" Subject: RE: Re: M14PEngines-List: 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 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 wrote: From: DAVID STROUD 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 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 wrote: From: markgreenway Subject: M14PEngines-List: Why would my Yak 52 m14p lose power? 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 _____ D======================== ========= D======================== ========= D======================== ========= D======================== ========= ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message m14pengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/M14PEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/m14pengines-list Browse Digests http://www.matronics.com/digest/m14pengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.