Thread: MS310 cylinder

I picked up a used cylinder for an MS310, to replace one on a saw of mine that had stripped out plug threads. Today I was installing it, and I found out that it's too big (the bore). Is it possible that there was 2 sizes used on this model, or is it simply not for a 310?

I do not believe the cc's have ever changed on the MS310. Though what you might be working with is a MS 290 believed to be a MS 310, or a MS 310 that is really a MS 390.

I have had good luck on those cylinders with stripped plug threads using a thread insert to repair instead of changing the cylinder.

Good Luck.

Originally Posted by Brad101

I do not believe the cc's have ever changed on the MS310. Though what you might be working with is a MS 290 believed to be a MS 310, or a MS 310 that is really a MS 390.

I have had good luck on those cylinders with stripped plug threads using a thread insert to repair instead of changing the cylinder.

Good Luck.

Well the saw says MS310 on the starter cover, and as far as I know everything is original.

Unfortunately, the old cylinder was the victim of a botched thread repair job (NOT done by me) Whoever did it drilled the hole out too big and totally ruined it.

What I meant to say on the last part of that is a MS 390 cylinder instead of a MS 310 cylinder.

Sorry.

It is possible the starter could have been changed at some point. The only ways to know forsure would be to measure the piston in mm's. Or run the serial number through a stihl dealer.

The 290, 310 and 390 series can use the same p&c on all of 'em. If the bore is too big, you may have a 390 cylinder. What does the cylinder measure?

Here are piston sizes:
290 46mm
310 47mm
390 49mm

I think the bore size is written somewhere on the side of the cylinder.

Well I measured the bores and it's 47mm on the original cylinder, and 49mm on the new used on that I got. That would be from an MS390, correct?

I had a 290 cylinder and a 039 cylinder. The 290 one said 029 on the side, and the 039 one said 039 on the side. I doubt an 310 cyl would say 031, since they're different saws. What's the cyl say on it?

Originally Posted by Edge & Engine

Well I measured the bores and it's 47mm on the original cylinder, and 49mm on the new used on that I got. That would be from an MS390, correct?

49mm is 390/039

Originally Posted by B200Driver

I had a 290 cylinder and a 039 cylinder. The 290 one said 029 on the side, and the 039 one said 039 on the side. I doubt an 310 cyl would say 031, since they're different saws. What's the cyl say on it?

I'll look tomorrow. Thanks for the help.
I have to decide what I want to do, I'll probably have to sell the 390 cylinder and try to find the right one for a 310. The reason is that the saw is for resale and even if I say it is the equivalent of a 390, the buyer would have no reason to believe me sight unseen.

Put an ad on here. You will have NO trouble offing a 390 cylinder. I bet you got a few PM's on it already.

Just get a 390 piston.

P.M. sent.