Terrence Jefferson
ArboristSite Operative
I'm sure you can find rings online and when you hone the cylinder just go easy as to not wear through the nikisil liner in the cylinder.
Saving Scored Piston
- Thread starter lil171
- Start date
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Clean the cylinder up and put new rings, it will be a runner and after about 5 tanks it will have nice compression. On a saw like that though just buying new rings as far as worth goes is like throwing good money after bad. I had a nice yellow Poulan OEM 40cc original with no scoring and it brought $20 on line....the guy did give me good feedback as it started for him in three pulls.
Brent Nowell
Addicted to ArboristSite
Where can he get a hone? I want to know too
Auto parts store, brake cylinder hone. Amazon has some 10.00 to 15.00 $$
Terrence Jefferson
ArboristSite Operative
I just use a 3 stone hone from the parts store . Use it with clean oil and go easy. Use a fine grit hone. They don't work on cylinders with open transfer ports.
Brent Nowell
Addicted to ArboristSite
Thx for the info Todd, is there a particular home you would recommend for saws?
Huskybill
Addicted to ArboristSite
You need a hone for nikasil cylinders. A cast iron hone won’t touch it. A scotchbrite hone can open up the bores too. I’ve seen them used to remove the galling and end up with a tapered bore in the end. Sometimes after honing more galling might appear with imbedded piston material. The difference is the color of material in the score marks is the clue.
www.enginehones.com
https://www.enginehones.com/flexhones.html
What about bead blasting the piston skirt last after cleaning it up. This would expand the metal somewhat? Or knurling it.? Then mic the bore and make the piston .002” small than the bore.
www.enginehones.com
https://www.enginehones.com/flexhones.html
What about bead blasting the piston skirt last after cleaning it up. This would expand the metal somewhat? Or knurling it.? Then mic the bore and make the piston .002” small than the bore.
Well so far no luck on teh rings locally, but have a couple more places to call. Took another quick peek and saw a small piece (approximately 1/4" square) of the lowest part of the piston has broken off(sorry, no pictures, phone was not with me). So now I am thinking I would have to completely remove the engine, disassemble it completely to find the missing piece, then reassemble with new rings, and more-than-likely a new piston. I am still not writing it off if I can find the rings locally. I may invest a few dollars in them to try, but that is where I will call it quits on this saw. Got enough other saws to use, and I did buy a case and the saw was free. Only to find out that no other saws of mine fit the case....... Regardless, this was a fun little project that did not realy cost me anything, and I had my money's worth of fun, entertainment, and most importantly, spending some time working on it with my dad! I will be keeping the bar, chain, carburetor, and some other little bits. Thank you to all for your help, encouragement, and time.
Huskybill
Addicted to ArboristSite
Take a coat hanger make an L shape and fish under the counter weights. Either turn the saw upside down and I seen a parts washer to wash out the crankcase. Sometimes it works sometimes it dont. I purchased a locked up 298 the piece was wedged in the crankweight.
So if I find rings, would it be alright to run it with the damaged piston (small piece broken off)? I will try to get pictures of the piston next week when I will next have some free time to play with the engine.
Yer saw, yer time, I wouldn’t sell it if it runs.
