what do these piston pictures tell you
- Thread starter wildman ben
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I'd be happy to buy one that looked like that. Doesn't mean the saw is perfect but at least that part looks pretty good..
what he said, looks fine,,
It`s not burning the best grade of mix oil but a few tanks with Seafoam in the mix and it would clean right up. That carbon is not all caked and hardened so a fuel mix cleanup would suffice.
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What everyone else has said........ but I would add that though that piston shows no scoring or other visible damage, that doesn't mean that the piston isn't worn out....I picked up a 49SP one time and the piston looked similar, however when I pulled it apart to replace the ring I found the piston worn to nearly 0.022" undersize!!!!!! No trauma...just plain old wear.....been up and down to many times.
Hope that isn't the case on your P&C (and probably isn't) but just saying that the visual through the EX port it, though a good start, is not always a firm indicator of actual fitness for use.
Hope that isn't the case on your P&C (and probably isn't) but just saying that the visual through the EX port it, though a good start, is not always a firm indicator of actual fitness for use.
I had a 5100 Dolmar that looked like that but the rings had so little tension that the saw wouldn't run. A new set of Cabers fixed it! Then I got another one exactly the same way, wondering if maybe they had a bad run of rings on that model of saw. I still have the second one and it runs fine two years later but I admit I haven't used it much..
mkinslow
ArboristSite Guru
How much seafoam would you recommend to put in the mix for this solution
It is usually the very bottom of the intake side skirt that wears the most on the vertical cylinder saws. I have seen and repaired a good many where the skirt wore so thin it broke off and stuck the saw, hard to believe some owners wouldn`t hear that rattle or notice the loss in power before the piston let go. In te picts above I believe I can still see the machining marks on the piston above the rings, doesn`t mean the rest of the piston is great but usually a good chance it is if usable shape but not new.
I use approx 4 oz per gallon for cleanups, works great but even more could be added as it won`t harm an engine in my experiences with it. We use it in every engine that sits for periods from all the air cooled to outboard engines it keeps them in top shape.
mkinslow
ArboristSite Guru
Good deal thanks
I'll second the seafoam and better oil at 40 or 50:1
I can pull a jug off one of my chainsaws after 100 hours of cutting and wipe the carbon off the piston crown right down to the bare aluminum with one swipe of my thumb and I run 40 to 1 in all my saws. More important to run the saw wide open through all types of cutting situations, run them hot and hard, that keeps them clean.
Amp4027
ArboristSite Operative
Dirt has been getting in there, so it needs a new airfilter and made sure that the airbox is secure with no leaks/bypass where dust can get in.
Looks like he has been using outboard/watersport 2stroke mix, or running the saw at half-speed, or has a weak spark/wrong plug temp. Could possibly be blow-by from chipped ring (at the index pin), but more than likely the guy is just running it pig rich with 40:1
Not a saw expert, so just take these opinions at face value.
Looks like he has been using outboard/watersport 2stroke mix, or running the saw at half-speed, or has a weak spark/wrong plug temp. Could possibly be blow-by from chipped ring (at the index pin), but more than likely the guy is just running it pig rich with 40:1
Not a saw expert, so just take these opinions at face value.
