redoing the cylinder?

[thompson1600]

Can you hone the cylinder of a chainsaw and put in a slightly oversize piston or with the head do you have to replace the whole thing? This would be for a scored cylinder. thanks

Tom

 

[eyolf]

I believe that some of the very old chain saws may have had oversize pistons available to allow rigid honing out the cast iron liner in the cylinder. By the mid-1950's, however, most makers were able to get chrome plating to hold onto aluminum in a jug.

The short answer is that you'll need to replace the whole assy. Many times an older saw just isn't worth the expense...retail is over $300, for example, on many saws.

 

[thompson1600]

figured so

Thanks. thought that would be the answer but was hoping.

Tom

 

[tundraotto]

bollocks! a lot of the time one can replace the piston on an old jug and have it serve well for a long time.

 

[jsikkema1]

If the scoring isn't into the chrome liner and most times its just aluminum galled onto the hard chrome you may be able to salvage the cylinder. The chrome is real thin and only a few thou or so. I have used acid to disolve the aluminum deposits with a Q-tip and some time... Hydro floric acid I believe will disolve AL but will have little effect on the chrome- please double check that. Then a ball hone to re X-hatch the cylinder. Will need a new piston and rings but they are a lot less than a complete kit with a cylinder

Jeff

 

[Mike mandry]

I have yet to do it, but have looked into doing so. It is possible to have a cyl. re-chromed. First it has to be "Stripped" of the old chrome, then "Finished" & then rechromed. Do not get chrome and hard chrome mixed up. hard chrome is much more expensive than decorative chrome. Not many people do hard chrome, but it can be done. I deal with it everyday in my job. I rebuild industrial control valves. I am always having shafts & the balls from ball valves re-chromed. It is expensive however. i would guess around $100-$150 for a cyl. to do a strip & rechrome.
When properly done, hard chrome is tough as nails & it should be as good as a new on if done right.

 

[eyolf]

I've heard of the acid thing; even tried it with HCL...took a long time, but it worked. I don't know where a guy would get HFl, but you can get HCL at the hardware store (cleaning pool filters, etching stains from brick, etc.).Sulfuric acid for a battery might work, too. Be mighty careful...I've got faint scars on one arm from fooling around with nitric acid in high school.

But the thread parent said scored, which I took to mean a scratch, like from a busted ring...different than transferred aluminum from the piston. Maybe I should have asked...the aluminum "wipe" is extremely common...