bang
ArboristSite Operative
I'm going to replace the engine in a 311 can I go bigger and use the parts from the311? if so what is the largest I can replace it with?
big bore 311
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Probably the 391. That's what I did. It's a lot of work. Clam shells are bear cats in disguise. Good luck!
bang
ArboristSite Operative
I did a 250 a while back, pia but I did it in 1 evening(might have gone a little into the next day lol).
Well then join the club. After you mount a 391 top end on that 291 beast, we will have both rebuilt the top ends on a pair of clam shells. All you have to do is count all the parts on the workbench. That's what guys keep telling me. I think those are the same guys that lost count of the parts as they took them down.
Don't forget to lay off the beers until after you are finished. Beers and clam shells don't mix.
bang
ArboristSite Operative
I may not be doing the big bore job after all. I found the 311 on cl, guy said he was cutting with it set it down and it was idling and just quit and wouldn't restart. He took it to a Stihl dealer and was told him something was wrong inside and at $75 an hour it wasn't worth fixing. I picked it up today (for cheap)and haven't had a chance to look at anything other than the outside but I pulled the rope and it has good compression with the decomp pushed in and it has more compression with the decomp pulled out. Maybe I'll get lucky.
bang
ArboristSite Operative
Well then join the club. After you mount a 391 top end on that 291 beast, we will have both rebuilt the top ends on a pair of clam shells. All you have to do is count all the parts on the workbench. That's what guys keep telling me. I think those are the same guys that lost count of the parts as they took them down.
Don't forget to lay off the beers until after you are finished. Beers and clam shells don't mix.
I said I wouldn't work on any more clamshels but I wanted to try one. Then I found a killer deal on the 311and here we go.
bang
ArboristSite Operative
Didn't get lucky, compression felt good because case was full of fuel.
Well, remember that when you rebuild a clam shell, the seals are then in reach and so are the bearings. You may need all three -- seals, bearings, cylinder kit. The dealer is right about $75 an hour being cost prohibitive. Even he probably can't rebuild one in less than 5 hours. So, add the parts in and now you are in New Saw City.
bang
ArboristSite Operative
I don't see any damage to the cylinder on the intake side but I see some dings on the top edge of piston on the ex side. The cylinder is probably bad but if not I'll replace the piston, bearings and seals. If the cylinder is bad I'll get a 391 engine from Huztl.
bang
ArboristSite Operative
Maybe I won't be able to use a China replacement engine. All I can find is 310/390. Will they swap into a 311?
Likely. Nobody here has been able to tell me the difference between a 390 and a 391 when it comes to the top end.
I've done a ton of those 290 to 390s this last year but still haven't had a 391 in the shop. Not sure I could do one with the lights out but getting pretty close..
I bet it took longer than... Hmm... At $75 an hour, I doubt very many saws could be rebuilt cheaper than a new one. Stihl has that all figured out also. Rebuilding them fast does not work. Make one mistake and you have lost it all.
I tell the guys I work for $500 an hour but I work fast...
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Well it is totally different to begin with...
I think we got a 291 in a few weeks ago that needed rebuilt and I couldn't do it because there's no aftermarket kits for the 291, at least in a good price range. The guy that owned it just took it with him and said he's gonna use it for parts for his other 291s. Certain Stihl saws don't have aftermarket stuff because they didn't make them very long, another example is the MS280.
Yeah, but other than that...
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Would it be easier to drill 4 holes into the cylinder, or from the bottom through the crankcase?
In what respect? You still have told us nothing.
