Stihl 044 help.

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
lone wolf
Joined
Oct 5, 2009
Messages
71,971
Location
Prowling The Pine Barrens
@pioneerguy600 @lone wolf
Here is the requested video. H and L Screws are set 1 turn each.

View attachment 1051249

It had run a little more prior to this but all were about the same result. With the need to choke, it feels like fuel delivery to me. But if I had the answers I wouldn’t be here.
First impression is the carb is not working right. But it could be a Vac leak. Vac test it again carefully and if good get a new OEM carb..
 
mudfly

mudfly

ArboristSite Operative
Joined
Feb 25, 2015
Messages
185
Location
NE MN
These also have a "factory design" air leak between the PTO shaft and the worm gear sleeve. Fill it up with thick grease before leak testing.
I did run into that when I rebuilt it. Had to come here to figure out how that was supposed to seal. Didn’t make sense then, or now, but I did get it to seal.
 
pioneerguy600

pioneerguy600

Lost in Space
Staff member
Moderator
. AS Supporting Member.
Joined
Dec 23, 2007
Messages
43,869
Location
N.S. Canada
@pioneerguy600 @lone wolf
Here is the requested video. H and L Screws are set 1 turn each.

View attachment 1051249

It had run a little more prior to this but all were about the same result. With the need to choke, it feels like fuel delivery to me. But if I had the answers I wouldn’t be here.
Just pulling this out of my hat here, are both the metal ring spacer and the collar washer that is needed in the end of the rubber manifold to keep the manifold flat for sealing against the back of the carb? I have found these missing on a few saws and it created an air leak even on saws that had tested fine on pressure n vac test.
 
stihltech

stihltech

Addicted to ArboristSite
AS Supporting Member
Joined
Mar 23, 2002
Messages
3,478
Location
western NY
A bit of explanation on the hi speed nozzle. It is not so much high speed operation to be concerned about. The nozzle has an internal check valve that must seat for correct idle. One symptom is that you need to choke the saw for restart. Also you cannot open up the low speed needle to get enough fuel to compensate. It is an carburetor internal air leak in essence.
It is time to back up , do the PRESSURE AND VACUUM TEST (otherwise your are wasting your time). Check spark with a spark tester (not a plug with a regular gap). You have been given all you need in all these posts to diagnose the saw. Let us know after the testing is completed.
 
billyboy

billyboy

ArboristSite Operative
Joined
Dec 11, 2017
Messages
289
Location
NW Iowa
Just curious as to why the rings look like they are recessed. Should’nt they be setting out at the edge of the piston or is it an optical illusion?
 
mudfly

mudfly

ArboristSite Operative
Joined
Feb 25, 2015
Messages
185
Location
NE MN
A bit of explanation on the hi speed nozzle. It is not so much high speed operation to be concerned about. The nozzle has an internal check valve that must seat for correct idle. One symptom is that you need to choke the saw for restart. Also you cannot open up the low speed needle to get enough fuel to compensate. It is an carburetor internal air leak in essence.
It is time to back up , do the PRESSURE AND VACUUM TEST (otherwise your are wasting your time). Check spark with a spark tester (not a plug with a regular gap). You have been given all you need in all these posts to diagnose the saw. Let us know after the testing is completed.
It's next on my list. Didn't have time last night. Time in the garage/shop is the one commodity that is in short supply.
 
Dean-O

Dean-O

ArboristSite Operative
Joined
Dec 6, 2019
Messages
237
Location
Jefferson
These saws are so easy to fix when I have them in my hands but trying to fix a problem over the net is like working blindfolded with my right hand ties behind my back. I have to commend mudfly for sticking with this thread and trying to solve his saw`s woes.
All day long the phone rings at my shop and a handful of times it’s someone wanting me to diagnose and fix there saw/lawnmower/string trimmer over the phone.

Sometimes I can help because the customer just flooded the unit, but other times I tell the customer to bring the unit in so we can look at it because it’s impossible for me to know what’s going on with nothing in front of me.

They keep going on and on, “should I buy a new coil?” “Is the piston worn?” “Maybe a new spark plug will fix it?”

The worst is the “it has no spark” 95% of the time the unit is burnt up and has plenty of spark. We tell this to the customer to pull the muffler and look at the piston and they insist they just need a new coil. I always tell them to bring the saw in and I will pull the saw over and pull muffler for them at no charge because if we sell an ignition once it’s installed we don’t take it back.

But to your point it’s frustrating trying to help customers over the phone that don’t want bring the unit in no matter what, even when we tell them we will give it a quick once over at the counter to narrow down what it could possibly be.
 
mudfly

mudfly

ArboristSite Operative
Joined
Feb 25, 2015
Messages
185
Location
NE MN
Just pulling this out of my hat here, are both the metal ring spacer and the collar washer that is needed in the end of the rubber manifold to keep the manifold flat for sealing against the back of the carb? I have found these missing on a few saws and it created an air leak even on saws that had tested fine on pressure n vac test.
I think the rings are there. This is how it looks today. Trying to get set up for vac test .439025B6-1AA6-4212-80C7-4B856844C850.jpeg
 
mudfly

mudfly

ArboristSite Operative
Joined
Feb 25, 2015
Messages
185
Location
NE MN
Pressure test results.

Held vaccum at -10 in Hg for 10 minutes.

Pressure started at 6 psi, bled down to 3 psi after 4 minutes. Bubbling out between the bushing and crank on the PTO side of the case. I did take the clutch and worm gear out so there is nothing pushing in on it to seal. It was originally installed with grease behind it.

2 things to note. Intake boot and impulse line were not included in this test. I don’t have a way to test with those on right now.
 
pioneerguy600

pioneerguy600

Lost in Space
Staff member
Moderator
. AS Supporting Member.
Joined
Dec 23, 2007
Messages
43,869
Location
N.S. Canada
I think the rings are there. This is how it looks today. Trying to get set up for vac test .View attachment 1051452
Yes, that is the two pieces I had asked about.
Pressure test results.

Held vaccum at -10 in Hg for 10 minutes.

Pressure started at 6 psi, bled down to 3 psi after 4 minutes. Bubbling out between the bushing and crank on the PTO side of the case. I did take the clutch and worm gear out so there is nothing pushing in on it to seal. It was originally installed with grease behind it.

2 things to note. Intake boot and impulse line were not included in this test. I don’t have a way to test with those on right now.
A strip of rubber behind the carb is all that is needed to test the intake boot.
 
mudfly

mudfly

ArboristSite Operative
Joined
Feb 25, 2015
Messages
185
Location
NE MN
Yes, that is the two pieces I had asked about.

A strip of rubber behind the carb is all that is needed to test the intake boot.
I was going to do that but I needed to hook the pump up to the barb for the impulse line. Can’t do that with the tank on the saw with what I have today. I can pick up a couple of other connecting pieces sometime yet this week to include those.

I figured that I would do the best test I could with what I had. It may not be perfect, but shows the crank seals and base gasket are all holding.
 
pioneerguy600

pioneerguy600

Lost in Space
Staff member
Moderator
. AS Supporting Member.
Joined
Dec 23, 2007
Messages
43,869
Location
N.S. Canada
I was going to do that but I needed to hook the pump up to the barb for the impulse line. Can’t do that with the tank on the saw with what I have today. I can pick up a couple of other connecting pieces sometime yet this week to include those.

I figured that I would do the best test I could with what I had. It may not be perfect, but shows the crank seals and base gasket are all holding.
The hose barb in a twostroke sparkplug base adapter works good for that test.
 
Mad Professor
Joined
Jul 2, 2007
Messages
18,246
Location
North East USA
I was going to do that but I needed to hook the pump up to the barb for the impulse line. Can’t do that with the tank on the saw with what I have today. I can pick up a couple of other connecting pieces sometime yet this week to include those.

I figured that I would do the best test I could with what I had. It may not be perfect, but shows the crank seals and base gasket are all holding.
Piece of tygon from barb to pres/vac pump.
 

Latest posts

Top