Mikhail Posted September 12, 2017 Report Share Posted September 12, 2017 (edited) Guys, Pleas help with your experience.... Crunked my Mooney after two weeks no flying and I have only 2000RPM at full throttle..... Prior this everything was fine Magneto working pretty good L&R, I have clean spark plugs, change gaskets and O-rings on the intakes, check the fuel flow on the fuel lines with aux fuel pump.... Prop is cycling, idle is smooth.... Tachometr is accurate, check the Prop rpm with Tru Tach.... Any advise what should I check next? Thanks for any tips! Edited September 12, 2017 by Mikhail Quote Link to comment Share on other sites More sharing options...
cbarry Posted September 12, 2017 Report Share Posted September 12, 2017 Things to consider: induction blockage or possibly prop cable/linkage binding or not allowing for full travel... Quote Link to comment Share on other sites More sharing options...
bob865 Posted September 12, 2017 Report Share Posted September 12, 2017 What is the manifold pressure at full power? Are you actually developing full power and not getting the RPM expected or are you not getting enough power to get past 2000 RPM. i.e. is it the propeller keeping you at 2000 or is it the engine not getting past 2000. Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 RPM is not getting above 2000, MP is around 2700... Quote Link to comment Share on other sites More sharing options...
rbridges Posted September 12, 2017 Report Share Posted September 12, 2017 I know you said your prop is cycling. Do the blades look feathered with the engine off? Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Yes, blades are feathered.... Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 12, 2017 Report Share Posted September 12, 2017 (edited) The blades should not be feathered when stopped. The blades should return to fine pitch with loss of engine power. If the blades are a coarse pitch while stopped, that suggests the prop is jammed at that setting. On the other hand, the props used on Mooney's should not be able to "feather" anyway, and the difference between fine and coarse pitch should not be terribly obvious. I think our prop guy (sorry, can't remember his name) just posted a video of the difference between fine and coarse pitch. Edited September 12, 2017 by jaylw314 Quote Link to comment Share on other sites More sharing options...
rbridges Posted September 12, 2017 Report Share Posted September 12, 2017 5 minutes ago, jaylw314 said: The blades should not be feathered when stopped. The blades should return to fine pitch with loss of engine power. Thanks for the clarification. I had a brain fart. I was completely on the opposite end of the spectrum. Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 English is my 3rd...sorry Prop is cycling with prop control... When shutdown the prop has flat pitch... Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Induction is clean, change the old air filter Bracket to new Donaldson then back to new Bracket.... No result Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted September 12, 2017 Report Share Posted September 12, 2017 12 minutes ago, jaylw314 said: The blades should not be feathered when stopped. The blades should return to fine pitch with loss of engine power. If the blades are a coarse pitch while stopped, that suggests the prop is jammed at that setting. On the other hand, the props used on Mooney's should not be able to "feather" anyway, and the difference between fine and coarse pitch should not be terribly obvious. I think our prop guy (sorry, can't remember his name) just posted a video of the difference between fine and coarse pitch. Cody Stallings Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 12, 2017 Report Share Posted September 12, 2017 What engine do you have, and what fuel flow did you see when you were at full throttle? You mentioned MP was 2700. I assume that was 27.0 inHg? That suggests your home field is around 3000 feet elevation? Do you have an engine monitor or EGT data on all cylinders or just one? How did you verify the magnetos are both good? What were the intake O-rings you mentioned you changed? Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 12, 2017 Report Share Posted September 12, 2017 Just now, Bob_Belville said: Cody Stallings Thanks, I'm terrible with names! Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Yes is 27....! Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 On EGT gage all cylinders showing close temperature. Mags checked at 1700RPM, the drop is as usual... Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted September 12, 2017 Report Share Posted September 12, 2017 Make sure that all 3 control cables - prop throttle mixture - are moving the levers stop to the stop. The throttle and mixture is on the front of the engine, prop governor on the back. If you're getting 27" MAP (what's your field elevation?) and the prop is full in you should be seeing RPM close to 2700. Do you have FF fuel flow? FF ought to get close to 18 gph with everything full forward. 1 Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Fuel flow full throttle 16gph. MP reading 28. Engine off MP reading 29. PA reading 580ft Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Quote Link to comment Share on other sites More sharing options...
Guest Posted September 12, 2017 Report Share Posted September 12, 2017 Tachometer accuracy comes to mind. The placard already says it's off by 100 RPM. Do you have access to a portable tachometer tester? Clarence Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Yes , checked it with True Tach, tachometer is pretty accurate.... Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted September 12, 2017 Report Share Posted September 12, 2017 34 minutes ago, Mikhail said: With MAP over 28" and FF of 16 (+/- 18 would be normal for take off) it appears there's a problem with the prop itself, the governor or the prop cable. You cycled the prop and the RPM came down (from 1700?). But you can't get it above 1900 which according to the tach label is really 2000. As suggested above, check to be sure that the prop cable moves the control lever on the governor from stop to stop. Quote Link to comment Share on other sites More sharing options...
Mikhail Posted September 12, 2017 Author Report Share Posted September 12, 2017 Find the problem it is prop itself.... removing tomorrow for prop shop... Thank you everybody for suggestions! 2 Quote Link to comment Share on other sites More sharing options...
Andy95W Posted September 12, 2017 Report Share Posted September 12, 2017 For your 3rd language, your English is quite good! Happy to have you here. 2 Quote Link to comment Share on other sites More sharing options...
Raptor05121 Posted September 12, 2017 Report Share Posted September 12, 2017 I had this same problem, it was the first indication my governor was leaking. I'd pop the cowling off and visually check thing before pulling a prop first Quote Link to comment Share on other sites More sharing options...
1964-M20E Posted September 13, 2017 Report Share Posted September 13, 2017 yes check your governor I've had a governor once that wold not allow more than 2600 RPMs. Changed governor and solved problem. Quote Link to comment Share on other sites More sharing options...
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