Poulan Pro PP5020 won't start

[Hammermechanicman]

Nice doorstop ya got there.

 

[virtual_guy]

It been straight fueled and the PNC is now toast. Depending how much you want to put in it but it is rebuildable.

I'm the only person who has ever put fuel in this saw and it has certainly always been mixed correctly. It may have been run lean, that I can't be so sure of. Would that cause the same damage? I'm not trying to debate your conclusion, just wanting to understand it.

Also, pardon my ignorance but what does "PNC" refer to?

 

[Hammermechanicman]

If your fuel mixture ratio was correct then either the saw ran lean for some reason or overheated or a combination of both. An air leak can cause it to run lean or a dull chain being forced into logs can overheat it. PNC piston and cylinder.

 

[ILENGINE]

I'm the only person who has ever put fuel in this saw and it has certainly always been mixed correctly. It may have been run lean, that I can't be so sure of. Would that cause the same damage? I'm not trying to debate your conclusion, just wanting to understand it.

Also, pardon my ignorance but what does "PNC" refer to?

It has been my experience that a lean overheat situation normally scores the exhaust port area, but a straight gas run normally will damage the cylinder all the way around with some exception were the galling on the exhaust port pushes the piston into the intake side causing damage.

 

[bertsmobile1]

other things that cause this type of wear are using starter fluid to start the engine
And running with too much oil that causes a carbon buildup around the port that breaks off & get stuck between the rings .

 

[virtual_guy]

So I'm the only person who has used this saw, started it, tuned it, or put fuel or bar oil in it. Unfortunately I think I know who's responsible. My goal now is just to decide whether I want to rebuild or replace it. And to learn enough to not do it again.

I'll inspect it more carefully when I take it apart but I suspect I overheated it while cutting the fallen hickory tree I mentioned in the OP. It was a monster and while the chain was producing ok chips, it wasn't as sharp as it could have been by the time the saw died.

Live and learn. And thank all of you for helping me with the learning part.

 

[Hammermechanicman]

Had a guy bring me a stihl 251c that he tried to fell timber with like Paul Bunyan. Dulled the chain and just kept on cutting. Scored piston, burned up clutch, burned up clutch drum, seized clutch bearing, melted worm gear and melted plastic case around the clutch. $250 doorstop now.

 

[StarTech]

That like the guy that brought a walk behind from Tramlaw, put fuel in it and started mowing his lawn before he knew it there was a hole in the side of the engine. Never put oil in it until after the hole was in it.

Manufactures don't allow for the brainless operators in their designs. They are counting the operators that actually have a working brain and a little common sense.

 

[virtual_guy]

Had a guy bring me a stihl 251c that he tried to fell timber with like Paul Bunyan. Dulled the chain and just kept on cutting. Scored piston, burned up clutch, burned up clutch drum, seized clutch bearing, melted worm gear and melted plastic case around the clutch. $250 doorstop now.

Yikes. I don't see any visible sign of overheating (other than the piston of course) and didn't smell anything out of the ordinary (I'm assuming you would smell a burned up clutch). Is it still likely that I have damage beyond what a cylinder and piston kit will fix? I would like to rebuild this thing but don't want to head down a bad path.

 

[ccheatha]

Yikes. I don't see any visible sign of overheating (other than the piston of course) and didn't smell anything out of the ordinary (I'm assuming you would smell a burned up clutch). Is it still likely that I have damage beyond what a cylinder and piston kit will fix? I would like to rebuild this thing but don't want to head down a bad path.

I took a Husqvarna I had to a local shop once. I had tried a 2-cycle mix that I didn't normally use and it was running lean. It got hot and bit the dust. One of the guys there took the plug out and shined a flashlight down the whole. He said, "dude your cylinder's scored. This thing is no good.". So I took it home. Was talking to a neighbor about it the next day. He told me that he'd dropped a tree on his (same model) and bent it all to heck. So he gave it to me. So I went to work disassembling the thing. Took the cylinder out and it was actually fine. Had a little oil streak on it, but that was about it. I figured it might be the magneto. So I replaced that with the one I now had for parts. I put it all back together again and it ran like a champ. When they do get to the point of shutting down after warming up, it can be a number of things. I like working on small engines, so I like the challenge, but sometimes it's not worth it. I like the Stihl I'm running now.