Need help with old Poulan chain saw

wilburn cox

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Yeah, I don't think you gave us a model number, so I don't have a clue what oiler setup you have just a guess going by the age and description. Most of those used a little diaphragm oiler that was pumped by the impulse of the crankcase, and if the diaphragm would crack, it would let bar oil suck into the crankcase and eventually into the combustion chamber.

the same scenario would occur if the carb was flooding, it would "hydro-lock", as the engine cannot compress a fluid.

to find out drain both the gas and oil tanks and thoroughly rinse with fuel mix. Drain for a day or two upside down, filler plugs and spark plug out/off/gone, and periodically pull the rope a bunch of times to thoroughly dry it out, do not have the plug
attached to the plug wire, or you could have a green flamethrower. After you are convinced that the system is totally dry,
reinstall the plug and pull it like you were going to start, with no gas or oil in it, and see if it pulls a lot better.

If it does, then add fuel mix only to the gas tank and try to start, off course leave the bar and chain off.

Thanks Fish; The model # is S-25CVA-38CCM. Yes it does have an impulse oiler and also a push button on top of saw that can be used to provide extra oil to the bar and chain.. I will try your suggestions when I have some time. I did open the bar and chain oil tank and cleaned it thoroughly. I did not notice any crack as you described but that is something I will definitely check out. IF a diaphragm is cracked, where is it and how can it be repaired or replaced.

Again thanks for your great advice.

Frustrated Texas (Red Cox)
 

wilburn cox

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Yeah, I don't think you gave us a model number, so I don't have a clue what oiler setup you have just a guess going by the age and description. Most of those used a little diaphragm oiler that was pumped by the impulse of the crankcase, and if the diaphragm would crack, it would let bar oil suck into the crankcase and eventually into the combustion chamber.

the same scenario would occur if the carb was flooding, it would "hydro-lock", as the engine cannot compress a fluid.

to find out drain both the gas and oil tanks and thoroughly rinse with fuel mix. Drain for a day or two upside down, filler plugs and spark plug out/off/gone, and periodically pull the rope a bunch of times to thoroughly dry it out, do not have the plug
attached to the plug wire, or you could have a green flamethrower. After you are convinced that the system is totally dry,
reinstall the plug and pull it like you were going to start, with no gas or oil in it, and see if it pulls a lot better.

If it does, then add fuel mix only to the gas tank and try to start, off course leave the bar and chain off.

Concerning your suggestions about the impulse oiler. I would almost bet money you are correct. I cleaned the oil tank when I had the saw dismantled but DID NOT dismantle the impulse oil pump. I had no idea what was actually inside the pump do did not go into it. Last night I looked carefully at my parts list with illustrations and saw the diaphragm you mentioned. Also saw many other parts included in the oil pump. I doubt if parts or a complete pump is still available for this saw. I will definitely drain gas and oil, flush all out, let it dry and try pulling the starter to see if it makes a difference.
If you know where I can get parts for the pump or a complete pump I would appreciate a web site or location. Even if parts/pump is available it may be expense prohibited.
Please respond and many thanks

Red Cox
 

Fish

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I see a diaphragm on e-bay for $39.99, I would have to do some scrounging to see if it would work, as your exact model doesn't readily pop up on the usual lookup sites, pretty high for a diaphragm.
 

friedfolk

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Crank bearings are probably half froze up and need replaced. Also check for dirt and debris on clutch side around the clutch and sprocket also.

It could also be a completely plugged exhaust system. If the saw was run with rich fuel, the excessive oil can plug up the slots in the muffler. This condition will cause the kick-back too.
 

DavePok

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I have just begun experiencing identical symptoms on Poulan P3314. Had been using the saw regularly for years. Replaces the bonnet and piston assembly about 12 months ago and it ran like a champ. Then one day - after running for a while I put it down to move logs into position for more cutting. Pulled the rope and I would describe the kickback as if the timing was wrong.((side note: I had seen this behavior with a lawnmower that hit a stump. Yup -sheared off the key that aligns flywheel to crank shaft - replacing the half moon key solved that one.)) So my first check was the flywheel. This is one of those all aluminum deals with the key a part of the molding in the flywheel - in other words - no separate half moon key. But the flywheel was intact and key undamaged. Reassembled it carefully to ensure key nested properly into the crankshaft slot. Still same symptoms. Spark lug removed and no excess fluid came out. Pulling the starter rope without the plug it spins freely. Chain brake is not locked, I can easily rotate chain with my hand. I had very recently removed the muffler and cleaned the screen or all carbon. Suspicious this was only 1 or 2 sessions before the issue started - but I'm sure carbon in the muffler is not the issue.

I'm also an old fart who needs to know what is wrong so I'll disassemble this puppy until I can find it - but I'd like to know what the original poster had finally found on his saw. What repair worked for you?
 

shadetree#1

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You probably need to start a new thread about your Poulan. this one is 7 years old.

Take the spark plug wire off and crank. If it turns over ok with no spark to the plug it's slightly out of time. (timing too fast) This can be caused by the magneto and if it's electronic ign replace the magneto or increase the magneto air gap to delay timing. (also if the spark plug gap is carboned so as to reduce the gap will cause timing to be too fast. Install a new properly gapped spark plug and gap the plug on the high side of the gap so as to delay ign timing.

If it still cranks hard with the spark plug wire removed, the crankcase is probably flooded and piston is hydro-locking due to maybe a bad carb. (flooding)
 
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