Marks in cylinder questions/ scoring

[Welderman85]

Hello all this was a reman saw so the marks could have allready been there I guess. But I did a bunch of cutting and it ran great. But the jug looks like this. Can I still run it. The pistion looks good

 

[pioneerguy600]

I have only seen that sort of damage get worse with run time, it`s always better to pull the jug off and clean everything up. There have been times I had to keep a saw with some damage running for a short period of time until parts could arrive for repair, the damage only got worse but the saw did produce saleable wood product, didn`t explode or even seize the bore. Parts arrived and thedamaged stuff got swapped out, the saw went back to work. It would have been cheaper to have pulled the saw down and fixed it right off but working remote at that time, parts took weeks to arrive.

 

[Welderman85]

What would have caused this. It was running great. I probably could have richened it up a bit but it ran good

 

[pioneerguy600]

Scratches on the exhaust side is caused by heat, heat is caused most times from lean conditions often caused by air leaks or the carb being set too lean on the H screw. The engine will rev much higher and friction between the P&C increase, there is less fuel incoming to cool the piston and then the piston swells from overheating and scuffing of the cylinder results. Not enough oil in the mix can also cause scoring due to not enough lube for the cylinder walls, that can cause scratching from all sides of the cylinder.

 

[NSEric]

There's a lot of carbon build up on the piston and exhaust port, if it gets hot enough to burn and flake off it scratches up the cylinder. I bet the muffler is full of it too.

This is kinda common on saws that get used trimming trails or other work that has you only running the saw for 5 minutes at a time. The saws dont run long enough to get hot and burn clean, then one day when you run the saw for a long period of time they get hot and the carbon gets burnt out.

 

[Welderman85]

Thank you so is it junk or should I keep running it and it I keep running it will it eventually just get worse and die. Thank you

 

[pioneerguy600]

Take it apart and try cleaning it up, then show us pics, easier to determine after cleanup if its good or junk.

 

[Franko]

Hello everyone
I will join the topic.
I have to replace the piston, but how do you rate the cylinder??
I cleaned it of carbon, the photo shows the damage but it is smooth.
Do more with it??

 

[Joedangelo04]

Run it