Why does chainsaw smoke so much when using it sideways to remove stump?

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cutter44752

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I cut down a couple big old dead trees and wanted to remove the stump at the bottom to make it flat...obviously it's the widest part of the trunk so it slightly exceeds the length of my bar which mean it's slow going but my saw smokes like a mofo when I do this (doesn't when I make vertical cuts). Is this because the oil isn't dripping into the bar when it's held horizontally (although it should be designed to do that you would think) or the fact that there's a lot of friction and sometimes the weight of the stump pushing down on the sawchain (which gets a lot hotter and has to be tightened much more than usual).

Can post a video if folks want.
 
Are you sure it is the chain smoking? It would still seem a bit odd but its is possible that if it is not the chain, there is more fuel getting to the engine that usual. I often get slight differences when tuning saws, depending on the way I tilt the saw. Not to that extent though.
 
Hypothetically, the engine builds up mix oil in the bottom of the crankcase when used in the normal upright position.

It’s out of teach from the crank counter weight and such.

When turned on it’s side the built up oil gets flung up the transfer ports ( or just runs there).

Hence, smoke.

That’s my theory and I’m sticking to it. [emoji6]
 
To confirm, do you suspect the bar & chain of smoking or is it exhaust smoke you're talking about?
If you mean exhaust, does it smoke out of the cut when you turn it on its side? Does it do it on either side? This can be the symptom of a failed crank seal & being tuned rich to compensate
 
That. And if you are cutting "at the bottom to make it flat" as you say, you likely are cutting into dirt and gritty debris which is a great way to instantly dull the chain.
That's possible, it also happened with a brand-new chain but I guess they can get dull almost instantly when they get stuck in the dirt a little.
 
certainly don't let any presser of the stump sit down on your chain. Use a wedge or stick.
yes you are going through the strongest fibers, as well, if it is flared then it is not a regular crosscut anymore.
2) As said, it got dull or wasn't 'sharp' enough for the task to begin
Good advice, I do have a felling wedge.
 
To confirm, do you suspect the bar & chain of smoking or is it exhaust smoke you're talking about?
If you mean exhaust, does it smoke out of the cut when you turn it on its side? Does it do it on either side? This can be the symptom of a failed crank seal & being tuned rich to compensate
It's exhaust smoke. I'll have to see if I can reproduce with the saw horizontally the other way, although it sounds like if I just sharpen the chain and use a wedge it might not happen.
 
although it sounds like if I just sharpen the chain and use a wedge it might not happen.
I think those comments were made under the presumption it was the bar/chain smoking.
If it's exhaust smoke it's likely you have a fluctuating air/fuel ratio, in that case my next step would be to pressure/vac test it
 
I cut down a couple big old dead trees and wanted to remove the stump at the bottom to make it flat...obviously it's the widest part of the trunk so it slightly exceeds the length of my bar which mean it's slow going but my saw smokes like a mofo when I do this (doesn't when I make vertical cuts). Is this because the oil isn't dripping into the bar when it's held horizontally (although it should be designed to do that you would think) or the fact that there's a lot of friction and sometimes the weight of the stump pushing down on the sawchain (which gets a lot hotter and has to be tightened much more than usual).

Can post a video if folks want.
What kind of saw?
 
It's exhaust smoke. I'll have to see if I can reproduce with the saw horizontally the other way, although it sounds like if I just sharpen the chain and use a wedge it might not happen.
It would be very odd to have white smoke coming out the exhaust. How do you know it is from the exhaust?
 
If it is white smoke then it is not exhaust. Remember that you are putting the "HOT" pto side down and blowing hot air off the cylinder and exhaust onto the ground, where it has no where to escape, and overheating the clutch components causing them to smoke.
 
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