Heya all, very new to the forum in terms of posting so forgive any mistakes in posting and such.
I have a 1958 182 with the O470L, it was field overhauled long ago in calendar time but fairly few hours in engine time as the airplane only put a few hours on each year for the past decade or so. I fly it a lot more often now, usually once a week minimum. I understand that the infrequent use was definitely hard on the engine.

The engine runs fine, a bit low on oil pressure in the heat of the summer but fine in the cold winter temperatures. Doesn't burn or leak enough oil to lose more then a quart every couple hours or so. I've noticed recently that the engine becomes stiff and hard to move after it has been running, so much so that the starter will not crank it over. When cold the engine moves freely, propeller bounces when pulled down, normal, starts fine.

I haven't a clue where to start and am going to ask my A&P tomorrow but figured I'd ask just to dip into the pool of knowledge here. I don't plan to fly it till I at least roughly diagnose it as its scratching me the wrong way.

Thanks all.

Make sure the mags are off and turn the prop by hand. Then go get it warm and do it again. That will take the starter/starter drive out of the equation. If it is a lot harder to pull when hot I would worry about main bearings starting to go. Pull the screen and do a oil sample. Using a quart of oil every 2 hours is definitely on the high side. My 0470L uses less than a quart between 25 hr changs. DENNY

DENNY wrote:Make sure the mags are off and turn the prop by hand. Then go get it warm and do it again. That will take the starter/starter drive out of the equation. If it is a lot harder to pull when hot I would worry about main bearings starting to go. Pull the screen and do a oil sample. Using a quart of oil every 2 hours is definitely on the high side. My 0470L uses less than a quart between 25 hr changs. DENNY

If I'm reading the OP correctly, I think that's exactly what he's saying is happening.
Weird issue for sure. My first concern would be main bearings as well. Be interested to see what an oil sample came back for metal content.

Not trying to alarm you but my old 470K (I have a 520 now in my 1958 C180A) did the same thing prior to it producing a lot of metal. It just got progressively more difficult to start - until it didn't start. Engine was full of metal. Went with the 520 back in 2008.


Josh

DENNY wrote:Make sure the mags are off and turn the prop by hand. Then go get it warm and do it again.

Yes sorry for not clarifying this. I have moved it by hand that’s where I found its stiffer. I noticed after a shutdown that it stopped more abrupt then normal and i went out and played with it. I’ve hand propped it here and there and can say the stiffness is so much so that it would make hand propping near impossible/dangerous, as there’s no bungee effect when pulled down hard.

My A&P and me are chatting but he’s never seen anything of the sort. The 170B forum had a similar topic in which OP eventually blamed piston pins & carbon build up and I’d read something about crankcase fretting somewhere else (terrifying).

All in all it doesn’t sit well with me so I think the main bearing thing might have some possibility.

Dog is my Copilot wrote:Not trying to alarm you but my old 470K (I have a 520 now in my 1958 C180A) did the same thing prior to it producing a lot of metal. It just got progressively more difficult to start - until it didn't start. Engine was full of metal. Went with the 520 back in 2008.


Josh

What’s strange is I haven’t the slightest problem when starting cold, the engine spurs to life on the first cycle. It’s only when warmed up a little does that engine become stiff and unwilling. I do fear the worst though.

Wonder how much carbon is built up inside the piston ring grooves? The carbon expands when hot making it difficult to turn. Never heard of an aircraft engine with that problem.. old school automotive quite often….along time ago


Sent from my iPad using Tapatalk Pro

If you and your mechanic think it might be carbon in the ring grooves you could pull one jug and check. Always start with the easy things first so pull the screens, cut open the oil filter, then bore scope all cyl looking for signs of a tight piston. Do all that and anything else you can do before you pull the engine and crack the case open.
Good luck
Shane