Chainsaw won't re-start when Hot

[Iplayfarmer]

I've got a cheapo poulan chainsaw that I bought a few years ago for $5 at a yard sale. It's worked great for what I've used it for. I mostly just use it to trim small branches and occasionally cut a bit of firewood for camping.

The problem with it is that if I shut it of after it's warmed up, I can't get it to start again until it's cooled down.

Any ideas?

 

[amaxwell]

Check the screws holding the carb. to the engine ,mine had gotten loose and was letting too much air in causing hard starting when warm.
Amaxwell

 

[bstillw]

I had a Poulan that did the same thing. I usually clean my saws with the water hose. Did it one day when it wouldn't start and gave it a pull and it cranked right up. So after that, when it wouldn't restart, I would just hose it down under a water faucet and fire it back up. Didn't try it, but if you are out in the woods a jug of water might accomplish the same thing. Do avoid spraying a lot of water in the exhaust, otherwise just douse it good. Don't know if it was vapor lock or what but I didn't worry about what it was anymore!

 

[arrow]

It is getting hot for one of 4 reasons. !. Change out the spark plug and clean the fuel filter. It may be running so lean because of insufficent fuel supply, that the ignition module heats up and will not start the saw until it cools down 2. The plug is bad enough so it will not send sufficient spark until it cools down. 3. The ignition module is on the way out (I've seen ignition modules mostly just fail. There was one guy I worked with though whose saw was doing something similar to yours and his shop said it was the ignition module) 4. You are getting vapor locked.

 

[Iplayfarmer]

It is getting hot for one of 4 reasons. !. Change out the spark plug and clean the fuel filter. It may be running so lean because of insufficent fuel supply, that the ignition module heats up and will not start the saw until it cools down 2. The plug is bad enough so it will not send sufficient spark until it cools down. 3. The ignition module is on the way out (I've seen ignition modules mostly just fail. There was one guy I worked with though whose saw was doing something similar to yours and his shop said it was the ignition module) 4. You are getting vapor locked.

It must be #4 because when I spray carb cleaner down the intake it fires right up and runs for a few seconds. I've definately got spark.

 

[arrow]

You can have sufficient spark enough to start it but if the plug has reached its end, it will not keep the saw running as the insides heat up sufficiently enough to shut down current transfer. Clean out the fuel filter, replace the plug, For 2 bucks, you may not have to put up with this at all.

 

[ray66v]

It must be #4 because when I spray carb cleaner down the intake it fires right up and runs for a few seconds. I've definately got spark.

A lot of people have posted on the internet about vapor lock issues with the fine federal government subsidized fuels we now have.

Additionally, fuel lines and filters are often being eaten up particularly in garden equipment, sometimes causing restricted flow, aggravating the problem.

I recommend Replacing the fuel line, and filter. Look for the possibility of rerouting the line where its not as hot, (very little chance in a chain saw). And, if necessary, experiment with simple heat shields like aluminum foil, wrapped around the fuel tank, the carb, and fuel line.

 

[Tig]

I also agree on the fuel filter / vapour lock. My father's McCulloch does the same thing.

 

[Dmace]

Typically when a chainsaw wont start when warmed but starts and runs fine when cool, it's because the air/fuel ratio is too rich (too much fuel). It starts fine when cold because extra fuel is the same as using a choke. When it's warm and still too much fuel, it's flooding. Can you start a warm engine with the choke wide open... Nope.

Let it cool down and then start it, screw in the air/fuel mixture screw about 1/4 turn at a time and give her a few wide open runs between each turn until it sounds raspy or shows little to no smoke. When it does, turn it out 1/4 turn and try that out. After some use, keep an eye on the spark plug and if it looks white then you are too lean (too much air) and if it is back then you are too rich (too much fuel). You are looking for a nice light brown. For cheap saws, Poulan makes a good starter.

 

[RWEST]

I bought a few years ago for $5 at a yard sale

For 2 bucks, you may not have to put up with this at all.

But that's 40% of what he paid for it!!
Sorry - couldn't help it.

These are all good suggestions, BTW.