Stihl 044 air leak?

[Bill Krummel]

I picked up a well use 044 recently that needed a top end, I replaced that and put a new carb on it. it fires up ok but has a very erratic idle. The idle speed screw has no effect and the low jet only effects it temporarily, i know it's sucking air but I can't find where. I replaced crank seals for piece of mind and fuel line as well as impulse line. Could it be the carb? I did cheap out and buy aftermarket. Any help would be great!

 

[SteveSr]

I picked up a well use 044 recently that needed a top end, I replaced that and put a new carb on it. it fires up ok but has a very erratic idle. The idle speed screw has no effect and the low jet only effects it temporarily, i know it's sucking air but I can't find where. I replaced crank seals for piece of mind and fuel line as well as impulse line. Could it be the carb? I did cheap out and buy aftermarket. Any help would be great!

FYI, these have a nominal leak between the PTO shaft and the oiler spacer. I filled mine with thick high temperature grease.

Aftermarket carbs are a crapshoot. Why not rebuild the original?

 

[Bill Krummel]

I have just never had trouble with after market. I know a lot of people don't like them but I have used them on 2 other saws without issue, I will rebuild the original and se if the does it though.

 

[Vintage Engine Repairs]

Only you can answer that question by doing a pressure a vacuum test.

 

[Bill Krummel]

Ok I ran a pressure test this morning and saw no leaks, and I put a new base gasket on just to know it's new and undamaged. That seems to have helped with the randomness at idle but now it won't idle down. When I engage the chain brake I'd bogs the motor and the clutch will slip through it a little. The speed screw will idle it down a little but stops effecting it.

 

[rupedoggy]

Mabe a case gasket leak or, as was suggested rebuild the original carb.

 

[president]

Only you can answer that question by doing a pressure a vacuum test.

You need to tighten down the clutch to totaly eliminate
the pto side leak on p/v test or you will be scratching your
head to find the leak after a seal change