MS 260 Pro Chain Saw - the chainbrake is melting again

Just a quick question. I am running 2 MS 260 Pro's and the chain-brakes are starting to melt above the exhaust. I have replaced one already as it melted to the point it snapped. These saws are about 6 months old . I have racked my brain to see why this is happening to these new saws when it did not happen to the older 26 I traded them in for. My feeling is that they are missing an exhaust guard, but there does not seem to be anywhere for it to be mounted. i know on my old trusty Husky 257 there is an exhaust guard. Any ideas.

Post a pic of the exhaust outlet, my 025 melted the brake handle a little bit but that was from pulling it into the hot muffler. When it's running and cutting etc it's fine. There's usually a little vent style thing that redirects the hot air sideways toward the bar, maybe your muffler doesn't have it?

Also, the back of the brake handle usually has some silver foil stuff to deflect the heat.

I had the same problem with a new Husky. There was a small metal bracket on the muffler that deflected the exhaust right onto the chain brake handle. After melting one handle, I hammered it flat - problem solved.

Actually, the whole thing busted off the front of the muffler on the 025 this week and now it goes like the clappers ... I think I'll leave it! Little noisier though.

Wow, they're both doing it? I wouldn't guess that both are missing their aluminum tape.

Just brainstorming, and not at all to question your knowledge or usage, but you aren't by chance running them on stumps near the ground, running them too hard, or too lean, or any condition like that that will make a hot saw.

I wonder if a muffler mod would cool them off enough.

Dean? Ed? Anybody?

Jeff

What Stihl's in meltdown mode must be a hot saw there old mate i though Stihl stuff was infalable ?????????????????????????

Mc Bob..he he he.

I had warranteed out a couple of Stihls inthe past, where the muffler halves were not
mated together correctly, and exhaust was leaking out where it should not. This was
an actual defect, and not just put back together wrong by someone[customer].
Take a close look at them, and if it looks like a defect, take it by the dealer.

I have been extra careful with the mixing of the gas and have had the carb looked at. It is idling at the right speed and its top out revs are good too. I am going to take the whole thing off and check for any holes or cracks. Maybe my saw is feeling the way I am with this 95 degree weather. I may just end up making a few adjustments to the deflector on the front. Thanks for the input.

Fish said:

I had warranteed out a couple of Stihls inthe past, where the muffler halves were not
mated together correctly, and exhaust was leaking out where it should not.

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Thanks Fish I never thought of that, I have an 028 that I have changed the gasket on thinking that was the problem but it didn't solve it, the thing will cook you hand if you grab the front handle on the side of it. I was wanting a differant style muffler anyway, but it was driving me nuts trying to figure out if it was leaking around the gasket.

lostone said:

Thanks Fish I never thought of that, I have an 028 that I have changed the gasket on thinking that was the problem but it didn't solve it, the thing will cook you hand if you grab the front handle on the side of it. I was wanting a differant style muffler anyway, but it was driving me nuts trying to figure out if it was leaking around the gasket.

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Add my thanks to Fish. My MS310 is doing the same thing. Runs great, sounds great but the chainbrake and area below it get too hot to touch. I will be checking the muffler. This is a new problem that just showed up on my last outing.

Harry K

Stihl's with problems. Thought only the cheap poulans come up with those type of problems( meltdowns). Was cutting in 96 degrees the other day between the 3750 and the 330 with no meltdowns. Just some smoking very hot saws. Stihl must have a design flaw. hehehe, jerking the big dawgs chains.

After poking the dawg earlier. I thought I would look at the chainbreak design on the poulan 330. It has a heat shield between the case and chain break area that comes up into a triangle. With a small air gap to the chain break side and larger air gap between the case and muffler. Seems to be a good design, no scorching or burn marks there. Just thought this might help you make your own heat shield to save them poor expensive stihl's. jab jab.

I dont know if the 028 came with a heat shield between the muffler and the crankcase or not, my 036 and 046 have it, I cant find it in the ipl for the 028, I was thinking of buying one for the 046 then trimming it down and putting it between the muffler and crankcase on the 028.

turnkey4099 said:

Add my thanks to Fish. My MS310 is doing the same thing. Runs great, sounds great but the chainbrake and area below it get too hot to touch. I will be checking the muffler. This is a new problem that just showed up on my last outing.

Harry K

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Dropped it off at the professional saw shop (John's saws) in Lewiston, Id yesterday. Stopped today to check on it. He had pulled the muffler to check the gasket and heard a rattle from inside it. Put a new muffler on. He hadn't had time to run it to check the heat problem yet so I told him I would stop in again on Monday. I should have asked today but will on Monday for the old muffler so I can disect it to see what the problem is and let you all know.

Harry K