Painted myself into a corner.....

[John Lyngdal]

I picked up a Husky 351 the other day and a suckish price that started easy and ran well, but had a plastic intake clamp that I wanted to replace with a metal unity.
The first step was to pull the bar and chain, as the chain was dull muffler and a found that a gorilla had tightened the bar nuts. I couldn't budge them with a bar wrench, and ended up using a 1/2" drive ratchet to get the nuts removed. As I wanted to look at the piston skirt the muffler was the next target, and things when downhill from there. The side bolt was tightened to a nominal level, but the first muffler bolt was tight and broke loose with a pop. Now I'm onto the third and last bolt and it won't budge. I soaked the area with Kroil, heated the muffler screw with a propane torch, and gave it a rap of a hammer. Nada... Drizzled more Kroil down the side of the muffler and let it sit overnight. Then repeated the process trying to break loose the screw. Curses...Foiled again. At this point I thought I'd just put the bar with a sharpened chain back on, keep the area soaked in Kroil, and cut some firewood. Crap... The muffler gasket has slipped and I can't replace the other muffler bolt.
I ordered a 4mm impact driver which should arrive shortly to up my game. The last ditch effort being considered is machining off the bolt head so I can remove the muffler and directly access the threaded portion going into the cylinder.

Any other removal techniques/suggestions I have overlooked?
I already have a 346 OE and NE, but if things really crater, I can just install a 346NE P&C.

 

[huskihl]

Get the gasket back in place along with the other bolts and run it in some wood. It’ll come out easier when the motor is hot

 

[John Lyngdal]

The gasket had rotated to the point that there wasn't an edge to work on down the bolt hole.
The saw would still run at 12k rpm with the partially blocked exhaust port, so I ran it until the cylinder was up to temperature and gave the 4mm impact driver a go.
At the low torque setting the screw didn't budge, so I switched to the high torque setting and promptly spun the driver and rounded the hole.
It just so happened that a T-27 driver was sitting on the workbench and just slightly oversize for the rounded bolt hole. I drove the driver bit into the hole and gave it another session with impact driver on the high setting and a light touch on the trigger. Success! The bolt broke free and allowed the muffler to be removed. The added bonus was that I found a clean piston skirt.

Happy New Years!!!!

 

[Old2stroke]

I picked up a Husky 351 the other day and a suckish price that started easy and ran well, but had a plastic intake clamp that I wanted to replace with a metal unity.
The first step was to pull the bar and chain, as the chain was dull muffler and a found that a gorilla had tightened the bar nuts. I couldn't budge them with a bar wrench, and ended up using a 1/2" drive ratchet to get the nuts removed. As I wanted to look at the piston skirt the muffler was the next target, and things when downhill from there. The side bolt was tightened to a nominal level, but the first muffler bolt was tight and broke loose with a pop. Now I'm onto the third and last bolt and it won't budge. I soaked the area with Kroil, heated the muffler screw with a propane torch, and gave it a rap of a hammer. Nada... Drizzled more Kroil down the side of the muffler and let it sit overnight. Then repeated the process trying to break loose the screw. Curses...Foiled again. At this point I thought I'd just put the bar with a sharpened chain back on, keep the area soaked in Kroil, and cut some firewood. Crap... The muffler gasket has slipped and I can't replace the other muffler bolt.
I ordered a 4mm impact driver which should arrive shortly to up my game. The last ditch effort being considered is machining off the bolt head so I can remove the muffler and directly access the threaded portion going into the cylinder.

Any other removal techniques/suggestions I have overlooked?
I already have a 346 OE and NE, but if things really crater, I can just install a 346NE P&C.

Your Mr. Gorilla with the bar nuts is a pretty common new owner of chainsaws. They think that the chain is getting loose because the bar is slipping so they REALLY tighten the bar nuts. I have a nearly new Pioneer P-20 that the owner tossed because he stripped the bar studs and didn't want to pay a shop to replace them. Brute force and ignorance provides us with lots of saws.

 

[dboyd351]

Would be nice if they would stop to consider it is the chain tensioner, not the bar nuts keeping the chain tight.
Oh yeah, that requires thinking, not brute force - no cigar.

 

[Fatherwheels]

I would do as mentioned, assemble as best as you can, run it to heat it up,
then try to remove the tight stud, keeping the stud that came out in place,
that may help keep some of the pressure off the one that won't move.
If all else fails, use brute force, you will either break the stud and free the muffler,
from where you can weld the nice shiny break with a tig or mig, keep adding to the
length of it until there is enough to weld a nut onto, all this heat will probably make
the stud turn out without much effort, just be sure to plug up the exhaust port so no
sparks get in.
If all this fails, you still have the muffler and piston, and will need a new cylinder,
hopefully it won't come to that.

 

[av8or3]

Just put some serious heat from either a propane/mapp torch or oxy/acetylene to the boss that muffler bolt goes into and it will come loose. The aluminum will expand more than the steel and out it will come. Heat is your friend.