Stihl 044 help.

[mudfly]

I have an 044 that I have been fighting for some time. For the life of me, I can not get it to idle (stay running).

Here is what I have done so far. Cylinder was off and cleaned transfer from scored piston. New OEM piston and rings. New seals on both bearings. Put together, pressure and vac tested the long block. Reassembled.

Got it running, didn’t seem to want to idle. Took carb off, new gaskets, ultrasonic cleaned. Still wouldn’t idle. Spark tests strong with a tester. It’s jumping a 3/16” gap.

Installed a Different carb that was rebuilt by someone else. Same issue. Will start and run will not idle. Needs a lot of choke to pull fuel to get it started on both carbs.

Back apart. New fuel line and fuel filter. Checked for impulse, it blipped the gauge with each piston cycle, but just barely. Put back together. Same deal. I can get it to run but will not idle.

From the start I Have tried low jet all over the place from 1/2 turn out to 1 1/2 turns out (1/8 turn increments). No change in idle. High is set at about 1 to 1.25 turns out. Tried adjusting the idle speed screw no change.

Seems like either I’m not getting a good impulse. Or the fuel line is getting pinched. Or I have a massive leak somewhere. (But it tested good both pressure and vac).

Pic below shows fuel line routing. It doesn’t look right to me, but not sure how else it would go.



Any suggestions would be appreciated.

 

[pioneerguy600]

Ok ,I will be the first to bite. What does not seem right with the fuel line routing?
The Tygon line is just a part of the tank vent.

 

[mudfly]

Ok ,I will be the first to bite. What does not seem right with the fuel line routing?
The Tygon line is just a part of the tank vent.

I meant the black fuel line next to the carb. Hard to see in there with camera. There doesn’t seem to be room and it’s almost like it’s kinking as the carb slides back on the studs. Tried my best to straighten it.

Possibly not the problem, just looking for something I missed or am not thinking of.

 

[Evan]

When you pull carb off does it spray fuel in your face?

My first thought was you botched up the seal install. I actually botched a crank seal just a couple weeks ago. Luckily i had a few seals on hand and yanked the botched one out and was more carefull on attemp 2.

Runability ice found is nearly always seals or possibly plugged vent. Ive seen carbs idle but run horrible.

On that not ive found carbs that dont run for **** to but mist idle. Ivd also blamed carbs for bad seals mire than ounce.


It should run at 1 turn out and idle. If you cang get it to idle tear it down i bet seal visually is messed up and catty wompus on the crank no makkng a seal.

 

[mudfly]

When you pull carb off does it spray fuel in your face?

Not necessarily in my face, but fuel does leak out of the carb when I pull it off.

 

[mudfly]

My first thought was you botched up the seal install. I actually botched a crank seal just a couple weeks ago. Luckily i had a few seals on hand and yanked the botched one out and was more carefull on attemp 2.

I definitely wouldn’t put this past my limited abilities. Sounds like I need to take it back down to the seals again.

 

[lone wolf]

I would say do a compression test and post it.

 

[pioneerguy600]

I meant the black fuel line next to the carb. Hard to see in there with camera. There doesn’t seem to be room and it’s almost like it’s kinking as the carb slides back on the studs. Tried my best to straighten it.

Possibly not the problem, just looking for something I missed or am not thinking of.

That is the proper position for the fuel line on an 044, there is a very sharp bend in the line right under the carb, it bends sharply toward the left and then sweeps around upward to the inlet nipple on the carb. This can be a pinch point or at times a place where the fuel line will crack, very close to the grommet at the top of the fuel tank. These are my most favorite Stihl chainsaw, had this model in all forms for a little over 30 years now. I know I have owned more than 40 different ones by now but I still own my very first 044 I bought around 1990, these saws have cut very much wood for me, some years over 1500 cord of hardwood firewood. I cut the trees down and pull them out long length, buck them up at the landing using mostly 044 and MS440 saws.

 

[huskihl]

Oem or AM fuel line? The new oem green lines have rubber o rings around them to help with kinking and wear from rubbing on the carb

 

[edmxz2002]

Would a blocked air filter cause this? Higher Rpm pulling air better than idle?

 

[lone wolf]

Would a blocked air filter cause this? Higher Rpm pulling air better than idle?

Take it off and tell us.

 

[pioneerguy600]

Would a blocked air filter cause this? Higher Rpm pulling air better than idl

J ust the opposite, a dirty airfilter makes the engine run rich sort of like putting the choke on.

 

[mudfly]

Would a blocked air filter cause this? Higher Rpm pulling air better than idle?

Air filter isn’t on it when I’m trying to run it.

 

[edmxz2002]

J ust the opposite, a dirty airfilter makes the engine run rich sort of like putting the choke on.

That makes sense.

 

[mudfly]

Oem or AM fuel line? The new oem green lines have rubber o rings around them to help with kinking and wear from rubbing on the carb

OEM to start. It was on the saw and didn’t see anything wrong with it. Then I thought maybe partially collapsing where is takes the 2 tight bends @pioneerguy600 mentioned. So I put in a new aftermarket line just to compare. Runs pretty much the exact same.

 

[mudfly]

That is the proper position for the fuel line on an 044, there is a very sharp bend in the line right under the carb, it bends sharply toward the left and then sweeps around upward to the inlet nipple on the carb. This can be a pinch point or at times a place where the fuel line will crack, very close to the grommet at the top of the fuel tank. These are my most favorite Stihl chainsaw, had this model in all forms for a little over 30 years now. I know I have owned more than 40 different ones by now but I still own my very first 044 I bought around 1990, these saws have cut very much wood for me, some years over 1500 cord of hardwood firewood. I cut the trees down and pull them out long length, buck them up at the landing using mostly 044 and MS440 saws.

I bought it well used. It was a deal, until I really learned how bad everything was. My fault. Now it’s personal and expensive. I like the size and weight, just want to get it running correctly.

 

[pioneerguy600]

I bought it well used. It was a deal, until I really learned how bad everything was. My fault. Now it’s personal and expensive. I like the size and weight, just want to get it running correctly.

It should not take much, sounds like it is in good enough mechanical condition, maybe just the support side of operation, fuel, air and spark.

 

[pioneerguy600]

Ok, I read where you cleaned up a scored cylinder, a new piston and rings but what is the compression now, low compression will cause poor idle but allow WOT . Just take the front cover off the muffler, two screws and take a look at the piston, unless you can take a compression reading.

 

[mudfly]

Ok, I read whee you cleaned up a scored cylinder, a new piston and rings but what is the compression now, low compression will cause poor idle but allow WOT . Just take the front cover off the muffler, two screws and take a look at the piston, unless you can take a compression reading.

I’ll try to get compression tonight. Need to get the kids to bed first. It pulls over pretty hard, but maybe it’s low?

 

[mudfly]

Ok, I read where you cleaned up a scored cylinder, a new piston and rings but what is the compression now, low compression will cause poor idle but allow WOT . Just take the front cover off the muffler, two screws and take a look at the piston, unless you can take a compression reading.

Pictures below. Compression was only 140 psi, but I don’t think the rings have set yet.

Piston looks clean to me yet.



Tear down further to look at seals?