Saw wont idle, part 3: update....

[CaseyForrest]

Ok, I got the intake tube, impulse tube, and carb kit in. I did notice however that the high and low needles didnt have any O-rings on them. Its a wj48 carb.

It winds up fine, runs fine at wot, but wont settle into a nice idle. If I close the low needle all the way, against the seat, it will idle for a few seconds, but then stop. It idles best with the low needle closed, go figure.

All this started after Cylinder and Piston and gasket replacement with new Stihl oem parts.

Possibly time for a new carb all together? Will the wj 65 or 67 work with the older 066?

Oh, one more thing, it doesnt matter where the idle adjustment is set, it seems to make absolutely no difference.

 

[Lakeside53]

Sounds like an air leak Time for a pressure/vac test; very few carbs ever need replacing...

 

[CaseyForrest]

Ok, found the leak, under pressure. It was between the jug and gasket/crankcase. I dabbed a little high temp rtv under the gasket, and between the jug and gasket, it held 7# for over minute.

I also vac tested it, to 1 inch of vacumm and it passed that too.

Edit: I think it was 10 inches of vacumm, not 1

 

[Lakeside53]

Great!

Your story is like so many others.. and like you, I found (a long time ago) that pressure/vac test saves a ton of time trying to figure out what's wrong.

If my first "guess" doesn't solve the problem, I immediately set the saw up for a pressure/vac test. Even if that passes, I can now ignore leaks as an issue.