Partial power loss

For the love people, can you not see that if your engine is not making ....takeoff power, rated power, super power, power chords, power steering, magic power, etc. you can't say it's making power. No one says partial power where Glenn works, come on folks, get with the program.
 
It's commonly referred to as not making power, not making takeoff power, not making rated power. Engine died, engine quit, etc.
The use of certain terminology in the Part 121 world does not mean that it is common elsewhere.
 
Now you're being silly.
 
Try Lycoming Operators manual part 6 troubleshooting, let me know what terminology you find.
There is no requirement for GA pilots to restrict themselves to terminology in engine operators manuals. In fact, most rental planes don't even have a copy of one on board.

I bet the number of people who were confused by the title of this thread is VERY small!
 
This is what POA is turning into. I made a post about a flight in which I had an engine problem. Got some pretty good feedback and had a generally good conversation about such things. Then Bill Clinton shows up telling us what the definition of "is" is. It adds nothing to the conversation, the only thing I can see that it might add to anything is to inflate Bill Clintons ego. Hey, Bill Clinton, we get it!!! You know ****.....cool!! In closing, Mr Clinton, I will not be looking for any manual nor any terminology because it doesnt matter to this conversation. Try finding Monica and short of that go, uh hm, Monica yourself.
 
That's POA's "Bill Clinton", likes to start shet and usually doesn't know WTF he is talking about. Jerk comes to mind.
 
That's POA's "Bill Clinton", likes to start shet and usually doesn't know WTF he is talking about. Jerk comes to mind.
Its not just him, it seems many times a post is made and regardless of content you start to see the "youre doing it wrong" posts. Quite frankly, I debated posting about this at all because I figured it would turn into a fuster cluck. I expected to get questioned on run up, turning xwind too early or something. I didnt expect the definition of "partial power" to be the "it". It is just getting tiresome. I am sure Mr. Clinton means well and i am equally sure sure he knows far more than I do, but please, if you arent adding to the discussion in a positive way, then just leave it alone. I am about ready to ragequit and change my name to Felicia.
 
Well, the news is in and it isn't good. Mx say it was a stuck valve/bent push rod/shattered valve and something I don't really understand. I got this second hand from the owner, apparently there was something that broke into pieces and some pieces went into the case. Mx says he has been unable to get all the pieces out and therefore the engine will have to be removed and the case split. The engine has high time and I suspect there is an overhaul in its future.
How many hours on it when you bought it? Did you get a "good deal"? Is it near TBO?
 
How many hours on it when you bought it? Did you get a "good deal"? Is it near TBO?
It isnt my plane Jimmy, a friend just bought it and he lets me fly it. The engine is past TBO, @ 2200. He did get a good deal on the airplane and even if he has to overhaul the engine, and i am pretty sure he will, he will still be in the plane "ok". I am actually going by the airport today to have a look see for myself and talk to the Mx.
 
I have missed what type and what engine but an additional 25-30 grand total extra, including off and back on the airplane can't be a real" good deal. " better call Charlie!
 
I have missed what type and what engine but an additional 25-30 grand total extra, including off and back on the airplane can't be a real" good deal. " better call Charlie!
Its a Cherokee 140 O320. I would like to think it wont take 25-30k.
ETA, after I talk to the guy at the shop today and know a little more, calling Charlie may well be on the agenda, but i dont own the plane, so it will be up to the owner. Thanks for the reminder about Charlie though.
 
There is no requirement for GA pilots to restrict themselves to terminology in engine operators manuals.
No, there isn't.

I believe most people, operating in any environment that uses specific terminology, would strive to learn, and use, that terminology, and shouldn't be offended by being corrected.
 
Important to remember that GA has shrunk tremendously in the past thirty years. It's only natural that many good mechanics gradually left also unable to make a decent living and good older or younger ones are not like it used to be. Caveat emptor.
 
That's POA's "Bill Clinton", likes to start shet and usually doesn't know WTF he is talking about. Jerk comes to mind.
But he graduated from Yale law school whose law professor judged him to be one of his brightest students. How bout you. Anybody say that about you?
 
No, there isn't.

I believe most people, operating in any environment that uses specific terminology, would strive to learn, and use, that terminology, and shouldn't be offended by being corrected.
No one needs to be offended by what is said here.
 
I guess a shattered valve would cause some pretty severe vibrations. I would also expect a bit more of an RPM drop as well but hey, that's a good thing you came back and shut it down. Never would have guessed that. Glad you got it back in (mostly) one piece.
 
I guess a shattered valve would cause some pretty severe vibrations. I would also expect a bit more of an RPM drop as well but hey, that's a good thing you came back and shut it down. Never would have guessed that. Glad you got it back in (mostly) one piece.
I went by the airport yesterday, the details i got from the owner were not exactly correct. Stuck valve, bent pushrod and tube, shattered LIFTER. Pieces of the lifter are in the case which is what is requiring a tear down.
 
Still yikes! I don't like chunks of lifter floating around my engine. Tends to be hard on the lifter bore too. As we have been taught here, "your lifter came from together."
 
This sounded exactly like what happened to me about 6 months ago. Mine turned out to be a cracked cylinder head. I lost 1 cylinder in flight and was making about 1900-2000 RPM and shaking pretty rough and a metal grinding sound every few seconds.

Glad you got down safe. I had wobbly knees for a few minutes afterwards, but I flew another 22nm in that shape. Stupid me.
 
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If you take off overly rich at a high altitude airport (above 5000'), you will make "partial power".

Partial means partial. It could be any part except all or none (1% to 99%).
 
Would a pre-buy have discovered the issue?
Unlikely unless there were obvious signs of prior valve sticking or perhaps if the engine was exhibiting "morning sickness" when the mechanic ran it.
 
I once had a total power loss and mistook it for a partial power loss. Fortunately, I was within easy gliding distance of a runway. I found out it was a total power loss after landing, when I got slowed enough for the prop to stop windmilling. :eek2:

Since then, I have come to the realization that the same method can be used to find out if it is a total power loss as is used to confirm which engine is dead on a twin: pull back the throttle and see if the RPM (or manifold pressure) changes.
Just to be clear, as long as an engine is turning whether due to combustion or windmilling, moving the throttle will have a significant effect on manifold pressure. And if the RPM remains within the governing range (CS prop) the RPM won't hardly vary so the only way to confirm a total power loss on the gauges would be to close the throttle completely and look for a significant RPM drop. A better method is to perceive the change in thrust as you move the throttle and if you have EGT take a look at that gauge. When combustion ceases for whatever reason the EGT will fall rapidly.
 
Just to be clear, as long as an engine is turning whether due to combustion or windmilling, moving the throttle will have a significant effect on manifold pressure. And if the RPM remains within the governing range (CS prop) the RPM won't hardly vary so the only way to confirm a total power loss on the gauges would be to close the throttle completely and look for a significant RPM drop. A better method is to perceive the change in thrust as you move the throttle and if you have EGT take a look at that gauge. When combustion ceases for whatever reason the EGT will fall rapidly.
Good points.
 
Today it happened. I was flying a PA28-140 that belongs to a friend. I pulled it out, preflight was fine, runup was fine, everything in the green. The takeoff was fine, making full power and the climb out was typical. At 500' agl I begin my crosswind turn and the engine stumbles for a second but only a second and resumes full power. I continue my turn and at about 600' I lost 500 RPM and the engine began to run rough. It was still making power, just not full power, I continued my turn back to the runway. I announced my intentions and landed without any problems. I turned off the runway and began to attempt to find out what was wrong. Oil pressure and temp were fine. Fuel pump was on. I had pulled carb heat during the event, there was no change. On the ground it idled fine and a ground run up only got a very slight almost not noticeable miss. However, when I would go to full power, I'd only get 2000 RPM and a very noticeable engine roughness. I leaned aggressively to clean the plugs, that's not it. I parked it and looked everything over and can't find anything that jumps out at me. I probably left some details out, but what in the world could it be? I flew it last weekend and it was fine. The other guy flew it Thursday and it was fine.
water in fuel, high angle bank and it comes out the tank, stumbles the engine, level flight the engine runs fine and the water is now gone, pilot scratches head. :)
 
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