lego1970
ArboristSite Guru
I have a 55cc Craftsman Chainsaw. I've had it for about 2.5 years and it's been a good saw for my needs but in the last couple weeks it's been acting up.
It starts and runs great for about 10 minutes both at idle, thottling up, and at full speed, both without a load and under a load......then all of a sudden after about 5 to 10 minutes it starts to bog down under a load. It still will idle a little bit but barely. Then if I wait 15 minutes and start the saw again, it will once again run great for about 5-10 minutes then all of a sudden bog down and want to quit. When it starts to bog down, it's very sudden and acts like it's running out of gas, yet there will still be plenty of fuel in the tank, and likewise the bar oil is not running out either and the chain tension is fine.
I was thinking that maybe it's was running so hot that the rings where expanding and the engine was starting to seize up and that's why it seems to run fine after it cooled down, so I adjusted the carb to make it run a little richer and also made my fuel/oil mix with more oil, but that seemed to have no affect at all on it. So now I'm kinda thinking it maybe vapor locking or something along that line after it gets hot or maybe the coil is not working properly when it gets hot. I had a lawn mower that did sort of the same thing when it's coil got hot, but it would completely shut down, as where this saw will still kinda of idle.
Any ideas on what this could be and or info on how to check vapor locking would be geatly appreciated. However please don't respond with "Buy a Stihl", or "Throw it in the Garbage". I know the Craftsman is a inferior chainsaw, but I would like to stick with what would cause the engine to do that and not a chainsaw debate. Thanks for your time and suggestions.
It starts and runs great for about 10 minutes both at idle, thottling up, and at full speed, both without a load and under a load......then all of a sudden after about 5 to 10 minutes it starts to bog down under a load. It still will idle a little bit but barely. Then if I wait 15 minutes and start the saw again, it will once again run great for about 5-10 minutes then all of a sudden bog down and want to quit. When it starts to bog down, it's very sudden and acts like it's running out of gas, yet there will still be plenty of fuel in the tank, and likewise the bar oil is not running out either and the chain tension is fine.
I was thinking that maybe it's was running so hot that the rings where expanding and the engine was starting to seize up and that's why it seems to run fine after it cooled down, so I adjusted the carb to make it run a little richer and also made my fuel/oil mix with more oil, but that seemed to have no affect at all on it. So now I'm kinda thinking it maybe vapor locking or something along that line after it gets hot or maybe the coil is not working properly when it gets hot. I had a lawn mower that did sort of the same thing when it's coil got hot, but it would completely shut down, as where this saw will still kinda of idle.
Any ideas on what this could be and or info on how to check vapor locking would be geatly appreciated. However please don't respond with "Buy a Stihl", or "Throw it in the Garbage". I know the Craftsman is a inferior chainsaw, but I would like to stick with what would cause the engine to do that and not a chainsaw debate. Thanks for your time and suggestions.
sorry, couldn't resist.
oke: 
