Ms271 gasket delete?

[Ketchup]

So my friend got a stihl 271 for a song and started using it as a ground and 20" takedown saw. The saw is basically new, but weighs a lot and had no grunt at all.

Well he let me fiddle with it, so I opened up the muffler, advanced the timing and took the limiters off the carb. Now it runs better, but it's still pretty easy to bog down in bigger cuts. I told him if we bring up the compression he should get more torque in the cut (although that may not be true).

I don't see the saw as worth enough to do a full porting so we're going forward with a gasket delete. I don't know much about this model, but I see no reason not to try. So...

Anybody ever try to polish one of these turds? Can the squish get better without lathe work? Are there carb swap options? Anybody ever cut on a 271 jug with good results?

I should say that without Arboristsite I wouldn't know my exhaust port from a hole in the ground. Many thanks to the guys who have helped me already and hopefully will again! I'll put up some pics of the saw and it's mods this weekend.

 

[Cease232]

This is a clamshell. There's no gasket to delete.


Sent from my iPhone using Tapatalk Pro

 

[Ketchup]

Ah crap. Well, at least you saved me from pulling the cylinder before I realized what a dunse I am.

Any other quick and dirty options for a compression increase? Buy a better saw, right?

 

[blsnelling]

You can't "pull the cylinder". You'd have to pull the entire engine.

 

[Ketchup]

Got ya. Yet another reason not to mess with homeowner saws. I'm going to go feel stupid in private now.

 

[alexcagle]

You can't "pull the cylinder". You'd have to pull the entire engine.

*
I changed out a cylinder kit on a MS271 last week.
I did so without touching the flywheel or clutch/sprocket.
The bottom half will stay put for you. At least it did for me. LOL
Now, granted, they do suck as far as keeping saw dust from falling down on the clamshell sealing surface while you are cleaning and preparing for a new bead of yamabond. I hate them, personally.

 

[Ketchup]

Well, maybe when this saw acts up I'll go deeper into it. Anyone think it's possible to mill down a 291 piston to sub out in a 271 and improve compression? Never fiddled with either. I'm thinking there is probably not enough meat on the 291 piston to cut it that far and get it back to the right timing.

 

[cuinrearview]

Anyone think it's possible to mill down a 291 piston to sub out in a 271 and improve compression?

No, that's not how it works. I believe 291 had a different bore size. Not a lot of options with a clammy to improve performance outside of what you've done, outside of port work. Save your money and get a better/more powerful saw.