flyboy
ArboristSite Operative
I bought a Stihl 025 from a Stihl sales guy. It was his personal saw that he could not get to run right.
Basically it would run nice and strong then it would cut out all of a sudden. It is not as strong as my muffler modded 026, but it did pull just fine in the cut.
It has the low adjust only carb (walbro wt) and it was set very rich. I pulled the carb apart and found a BB sized hunk of Dirko in it (my guess is the Dirko was blocking a passage intermittently).
I was all set to press it back into service when I decided to do a compression test. It is only getting 135psi (I checked my 026 with the same tester for sanity....165psi). The piston skirts look new. The top of the piston has some slight pitting on one side. The entire cylinder is sparkly but shows no sign of scoring.
There is evidence that the seals were recently replaced. Pressure and vac tests pass perfectly. The bearings feel perfect and make zero noise. I was told that the saw has all new fuel lines and they all look perfect.
I'd hate to replace a perfectly good piston/rings, but the compression isn't quite what my other saws have. Maybe just doing rings and getting the saw split in 2 for a closer look is in order.
Where can I buy Dirko and how much is it? Can I just use copper permetex? Can I get the rings anywhere for a reasonable (sub $15) price?
What would you do? My gut feel is to put it back together and run it.
Basically it would run nice and strong then it would cut out all of a sudden. It is not as strong as my muffler modded 026, but it did pull just fine in the cut.
It has the low adjust only carb (walbro wt) and it was set very rich. I pulled the carb apart and found a BB sized hunk of Dirko in it (my guess is the Dirko was blocking a passage intermittently).
I was all set to press it back into service when I decided to do a compression test. It is only getting 135psi (I checked my 026 with the same tester for sanity....165psi). The piston skirts look new. The top of the piston has some slight pitting on one side. The entire cylinder is sparkly but shows no sign of scoring.
There is evidence that the seals were recently replaced. Pressure and vac tests pass perfectly. The bearings feel perfect and make zero noise. I was told that the saw has all new fuel lines and they all look perfect.
I'd hate to replace a perfectly good piston/rings, but the compression isn't quite what my other saws have. Maybe just doing rings and getting the saw split in 2 for a closer look is in order.
Where can I buy Dirko and how much is it? Can I just use copper permetex? Can I get the rings anywhere for a reasonable (sub $15) price?
What would you do? My gut feel is to put it back together and run it.