Tightening bar nuts

[Giles]

I had a young man bring his Stihl Ms390 chainsaw to me for a muffler mod and carb work.
I had to use a long 3/8 pull handle to remove the bar nuts.
I talked with him when I finished and he said the chain would continuously loosen up if he didn't.
He was not lifting the end of bar and would sometimes back off the tension screw.
Four days later, he stopped by to thank me, said it was a different saw and the chain stayed tight with only occasional tightening.
I have run into this many times and replaced many bar studs that were broken, stripped or pulled out!

 

[Egon]

Ahh-those were the days! Young and Strong.

 

[Gary Fowler]

There is not really an excuse for not doing something right now days. You can find instructions for just about any activity on the net although some you tube videos have to be taken with a shaker of salt but there is always dozens of videos to look at when you don't know. I use them a lot for how to disassemble guns many of which I have bought used so no manual.
What happened to Dads showing their sons & daughters how to do things like change a flat tire, righty tighty-lefty loosey and other good things to know (like how to tighten the chain on a chainsaw)

 

[JimRB]

My Dad did not have a tractor, a chainsaw, a weed wacker or a lot of other tools I own. He did not teach me gun safety either other than "Do not touch or your butt will get warm." I do download owners manuals for used tools I purchase. Most tools made in the past 20-30 years may have a manual online.

 

[Bud Soda]

My saw only has one nut

 

[Giles]

Many saws do, even the Stihl 200t and the 201t, have only one nut. If you look at them, bars are limited in movement by a key that fits in the bar center slot. Some saws will have a small round pin.
Most bars with two nuts are limited by the two studs.

 

[s219]

A lot of people clobber the bar nuts. I don't even use the full leverage of the scrench tool -- almost always choke up on it to be sure I'm just snugging the nuts.

Another problem I hear of often, is someone with a worn drive sprocket can't get the chain to stay tight and then do all sorts of other things fighting the problem.

 

[xyz123]

I had to use a breaker bar not long ago to break loose and dang spark plug.

Seen many plastic cases saws with the bar studs pulled through from folks over tightening.

Alot of folks dont know how to do a proper chain tension like you stated Giles.

 

[prs]

Universal torque specification: Tighten until threads begin to strip, then loosen one half turn.

I was cleaning my old Super XL/AO for storage this morning and thought to myself how well those nuts stayed set when not even turned in that tight. I was eighteen years-young when I bought two of those saws. Both are still running great now that I am 61. I assembled my second new chainsaw (if we count the Stihl pole saw I got three years ago) since that long past previous purchase just last night. A lightweight rechargeable electric EGO for limbing and trimming. It has a plastic knob for bar clamp and another plastic thumb wheel for chain tension.

When I am 101, I bet the Super XL/AO saws are still going, but the pole saw and the EGO? I very much doubt that.

prs

 

[NativeSon]

Ahh-those were the days! Young and Strong.

Now it's Old & Leery.

Charlie