Muffler Bolts Coming Loose

[crunch]

Stihl chainsaw MS291

I had to remove the muffler and since reinstalling it has come loose a couple of times.

What does Stihl use on the bolts or what do you use on the bolts to keep them tight?
Torx head bolts, I'm guessing about 10mm

Any help would be appreciated .

 

[Little Al]

I've had good results using the the locking agent used for securing the bolts on auto brake calipers. It seems able to withstand the heat, & also will allow removal if needed I more than sure "Locktite will produce a suitable goo to do the job

 

[alexcagle]

I use 266 loctite. Works great.
A word of advice; put it in the hole with a pick, or something small, not on the screw. It all ends up not where it needs to be. Then tighten the piss out of them.

 

[crunch]

I appreciate the advice thanks.

Last night I put the muffler back on with permatex blue before getting to your suggestions and if comes loose again I will try either one of the two you suggest

 

[Shagbark]

I had the same issue on my 385xp. I paid less than $1 for toothed "star washers". I have not
had to tighten since (7 years)

 

[Jasonrkba]

Clean the threads really good and put a little oil on them. As you tighten the bolts they stretch a lot more than you might think, that oil makes it easier to seat them all the way. And the little star washer is a good idea also.

 

[crunch]

More good info thanks
If my last install fails I will take extra care in cleaning the threads ,oil them up and use the star lock washers