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C180/pponk0-470-50/MT prop, Low RPM on takeoff

Ruffair

GONE WEST
Lower Chena
I have sent Flight Resource a support request on this subject, and hoping someone here has quick answer. Being its Memorial Day Weekend and all......

On takeoff was getting 2400-2500 rpm, then at speeds above 100 mph rpm would increase to 2600 rpm. Was trying to get 2700 on takeoff so....

Was instructed to loosen the jam nut on front of hub and turn adjusting nut "IN" one turn. (In to increase)

RPM's on takeoff now went to 2300 rpm, then at 100 mph rpms went to 2650-2700.

Now was instructed to reset adjustment nut, back to original setting. Now rpm on takeoff is 2000. At 100-120 mph rpm's are 2600.


So, is something else failing on us here, coinciding with adjustments...?

Kem
 
spiral cracked crankshaft at prop gov oil transfer collar? allowing oil to bleed out of the transfer collar? check oil screen for metal! we learned the hard way... so packed we couldn't get screen out easy...

burnt up transfer collar?(steel to steel fit... not much wear burns them up....)

do they use a hartzel style governor or mccauley style? (the operate backward of each other, as to when the PUSH oil into prop whether it goes flat or full pitch..)
 
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Assuming that you have been using this for a period of time and that it has been operating normally? This sounds like something to do with the governor or the controls which are attached to it. Broken, bent, loose, worn out controls at the governor? Prop control loose where the housing is fixed to the engine? If all is in good shape it would be wise to pull the governor to see if there is metal on the screen which is part of the gasket.

Is the governor control arm held firmly against it's high rpm stop?
 
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It does not sound like an engine power problem. You should get full RPM long before full throttle if the governor is working. It does sound like what "Mike" said might be the problem.
 
Update...

Airplane is going in the shop this week. No more flying it till fixed.

I'm hoping it's "just" a governor problem, Mike's idea sounds real expensive.... :(

All professionally done some 350 hrs and 2 1/2 years ago. This has been a slow developing problem.
 
we brought a GOVERNOR down from another of our planes when our pilot experienced the flat pitch problem....

we FIRST thought maybe the cable slipped... tightened it... stepdad flew it around patch... part way around bang! flat pitched...

Second we tried something else.. long time ago... same result!

then the third time, we swapped governor , this trip around patch it went over 3000 RPM, shook bad, and threw the alternator belt off!

my stepfather Windy got out, and said he AIN'T FLYING IT AGIAIN, he walked up to to prop and pulled it fore and aft, and you could flex crank and said crankshaft was cracked.... we pulled the oil screen, and it was PACKED with metal pieces...

this was the SECOND one he had been flying in with a cracked crank......

EDIT!
one other CLUE was we bought this plane from a LAWYER with a MISSING ENGINE LOG BOOK(that probably had a prop strike noted...) this event happened just about 200 hours after we bought it....

and thanks to a volcanic eruption earlier that summer we had to change all 6 cylinder within the first 10 hours of owning it.... it decided to start drinking quarts of oil per hour... you could SEE the ridges in the cylinder bore...

and then later one of our pilots wiped the gear off it landing at the dog salmon river camp of brent jones, first time Windy let one of our pilots land there, short place where the river was part of the strip... I remember Windy saying to him, if you don't touch down in the first 20 feet go around... he touched down right at the end! but about a foot to low for the river bank... left one gear there and the other folded back... nice 60 foot landing in a 185! the cover picture on my web site is that plane as my stepbrother and I salvaged it, we had it back on it's gear and running by lunch the next day after we got there.. no hoists, no lifts... just shoveling dirt under one side and rocking it the other way and shoveling dirt under the other side.. rinse and repeat, to get it up high enough to put the gear back in.... http://www.mcsrepair.com we rebuilt it that winter.. that was also when the FAA said said I REALLY needed to go get my A&P, as I was overseeing our 5 plane Air taxi without the piece of paper that said that was OK.... and my mechanic overseeing my work was in Cordova (with a handful of flight passes 'readily available' faa speak) so in 1991 I went to that little state of Texas and took a 'crash course' to get that magic piece of paper... also last time I was out of Alaska...5 of the 6 cylinder got cracks in that sudden shutdown...

trivia, that planes now? owned by jim west of wild west guns, or the TV show wildWest Alaska... 56J

ruff couple of weeks, that was either the first or second one, of the 2 out of our 3 185's we totaled in 11 days? insurance guy was not impressed, and in fact we were in transition to another carrier at that moment.... ugly next year, think mom said we paid $60k for next 9 months coverage... get rich in aviation!
 
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