Possible new bad gas. What should I do?

[ace4059]

I clean the filters regularly with compressed air. I’ve never noticed any damage to the filters. They were properly sealed. Each time I’ve cleaned them, the plastic air intake where the butterfly is, is always clean.
The only one I’ve had problems with sawdust getting past the filter was on the 500i which I ordered the Eagan air filter kit the first week I had that saw.

I personally don’t think it is front ingress of fines because I always maintain my equipment and take care of it and I would have noticed if it was dirty on the plastic where the air filter seals.

Now if it was carbon build up from the stihl ultra oil and damage from the carbon, I wouldn’t be surprised.

 

[lone wolf]

I clean the filters regularly with compressed air. I’ve never noticed any damage to the filters. They were properly sealed. Each time I’ve cleaned them, the plastic air intake where the butterfly is, is always clean.
The only one I’ve had problems with sawdust getting past the filter was on the 500i which I ordered the Eagan air filter kit the first week I had that saw.

I personally don’t think it is front ingress of fines because I always maintain my equipment and take care of it and I would have noticed if it was dirty on the plastic where the air filter seals.

Now if it was carbon build up from the stihl ultra oil and damage from the carbon, I wouldn’t be surprised.

Carbon would scratch the exhaust side.

 

[ace4059]

Carbon would scratch the exhaust side.

Thank you for that information.

 

[lone wolf]

Thank you for that information.

https://www.madsens1.com/how-to-read-a-damaged-piston

 

[sean donato]

At least my 400 filter seals very well, and hardly gets any fines past it. Doubt it's from debris.

 

[bwalker]

At least my 400 filter seals very well, and hardly gets any fines past it. Doubt it's from debris.

I've seen those sorts of marks on plated cylinders many times and they pistons show no scratching at all. I think this is alot of hand wringing and worrying about nothing. Although as I said before if the OP is worried pull the jug and inspect the piston.

 

[Tobystihl]

I've seen those sorts of marks on plated cylinders many times and they pistons show no scratching at all. I think this is alot of hand wringing and worrying about nothing. Although as I said before if the OP is worried pull the jug and inspect the piston.

I totally agree, seen lots of strange lines and marks, when looking through the exhaust port on newish saws, it used to worry me in the early days of saw rebuilding but its normal. If you run a plastic rod (or similar) across these lines youll find they don't snag.
Fuel up the saws and run them like you stole them....

 

[Khntr85]

I totally agree, seen lots of strange lines and marks, when looking through the exhaust port on newish saws, it used to worry me in the early days of saw rebuilding but its normal. If you run a plastic rod (or similar) across these lines youll find they don't snag.
Fuel up the saws and run them like you stole them....

Facts!!!

Got a 461 with really minor markings, runs like it’s fueled with meth at all times!!!!

 

[ace4059]

I tried a few different things to see if I could get them to catch on the vertical lines of the cylinder. I tried a plastic straw, , a wooden pencil, and a plastic pen. Nothing was dragging or caught. It all felt smooth so I think it looked worse in the pictures.

I can pull the cylinder if someone explains the process so I can run my finger over the marks. But honestly, I’m no longer worried.

 

[sean donato]

I tried a few different things to see if I could get them to catch on the vertical lines of the cylinder. I tried a plastic straw, , a wooden pencil, and a plastic pen. Nothing was dragging or caught. It all felt smooth so I think it looked worse in the pictures.

I can pull the cylinder if someone explains the process so I can run my finger over the marks. But honestly, I’m no longer worried.

Don't bother pulling them apart, the worst thing you can do is mess with something that runs right. No need at this point in my opinion. You did your due diligence.

 

[HansFranz]

Don't bother pulling them apart, the worst thing you can do is mess with something that runs right. No need at this point in my opinion. You did your due diligence.

I agree...If it ain't fixed, don't break it!

 

[Husky77]

A good reason to use Aspen type fuel (husky or stihl) I do and mix my own oil never any problems. On it's more expensive but for the amount I cut and times my saws sit on a shelf it works out great for me.

 

[Sidecarflip]

I had pretty bad gas this morning myself. Too bad it won't run a chainsaw but it did cause my wife to run away from me....

 

[lone wolf]

Facts!!!

Got a 461 with really minor markings, runs like it’s fueled with meth at all times!!!!

If it runs that good, maybe you might want to richen the H a tad.

 

[Khntr85]

If it runs that good, maybe you might want to richen the H a tad.

Oh no I have it tuned fat, it doesn’t have any marks you would even consider bad…

 

[Smitty Smithsonite]

Most of the time, light marks on the piston were made at time of assembly. The smallest amount of grit can make a nasty looking mark on a piston skirt. The rest of them usually is what got around, or through, the air filter. You wouldn't be able to feel any of the marks with a fingernail, MOST of the time. It's a non-issue.