Stihl 044

[NCFord]

Please don't get mad at me but I kinda "stole" a couple of saws the other day though not my fault. A friend of mine had a stihl 029 and 044 that his son ran some un-mixed gas in and ruined them, so I was told. This was about a year ago. I did not have time to look at them and told him to take it to a shop and see what the damage is and determine if it's worth fixing. He took it to a shop and was told both were "junk". So my friend tried to repair them and gave up, and called me the other day to see if I was interested. Since he had the 029 I figured I could at least use it for parts for my own 029 and he only wanted $50.00 for both saws, so I bought both.
So Saturday I started looking at the 029 and pulled the spark plug to check the compression the redneck way with my finger over the spark plug hole and thought it was very strong compression for running un-mixed gas. I could not hold my finger over the plug hole while pulling it over. So I put in a new spark plug and dumped the old gas out, and cleaned the air filter, then put in new gas and it fired right up! It ran like a champ!
I don't know what shop my friend took it to but they did not look at the saw very hard. I think they just saw an old chainsaw and said it was junk.
So that's the 029. The 044 is another story and this is why I am posting. It is seized. May be from un-mixed gas...I don't know. My friend said it did pull through after it stopped working but not now. I took the exhaust off and the piston is in the "up" position and the wall of the piston appear to be scored pretty bad. It seems like a rod is broken or something. I do what to get this saw running as I have always wanted a plus 60cc saw. So what am I looking at?

 

[claydogg84]

Please don't get mad at me but I kinda "stole" a couple of saws the other day though not my fault. A friend of mine had a stihl 029 and 044 that his son ran some un-mixed gas in and ruined them, so I was told. This was about a year ago. I did not have time to look at them and told him to take it to a shop and see what the damage is and determine if it's worth fixing. He took it to a shop and was told both were "junk". So my friend tried to repair them and gave up, and called me the other day to see if I was interested. Since he had the 029 I figured I could at least use it for parts for my own 029 and he only wanted $50.00 for both saws, so I bought both.
So Saturday I started looking at the 029 and pulled the spark plug to check the compression the redneck way with my finger over the spark plug hole and thought it was very strong compression for running un-mixed gas. I could not hold my finger over the plug hole while pulling it over. So I put in a new spark plug and dumped the old gas out, and cleaned the air filter, then put in new gas and it fired right up! It ran like a champ!
I don't know what shop my friend took it to but they did not look at the saw very hard. I think they just saw an old chainsaw and said it was junk.
So that's the 029. The 044 is another story and this is why I am posting. It is seized. May be from un-mixed gas...I don't know. My friend said it did pull through after it stopped working but not now. I took the exhaust off and the piston is in the "up" position and the wall of the piston appear to be scored pretty bad. It seems like a rod is broken or something. I do what to get this saw running as I have always wanted a plus 60cc saw. So what am I looking at?

I was looking for a 044 or 066 before I found the 372XP I just bought. Anyways, I would say the minimum you'll need is a new piston, rings, and head. I'm sure someone else who's more familiar with Stihl saws can give you a little more information. For $50, you got a pretty sweet deal anyways.

 

[TreePointer]

You also should check the shaft and bearings.

If you do get parts or a kit, make sure it fits your version. I can't recall all the details, but some engine parts for the 044 varied, so you have to confirm the proper parts by saw serial number.

The 044 is a favorite of some, so there are a lot of folks who rebuild them--especially on AS.

EDIT:

It's the 12mm vs 10mm wrist pin. See the following discussion:
http://www.arboristsite.com/community/threads/serial-number-help-with-an-old-044.185415/

 

[Jon1270]

With a scored piston, normally the first thing you'd do is figure out what went wrong. If you're sure the saw was straight-gassed then you can go ahead and take it apart. At a minimum you'll be removing the airbox assembly, carburetor and engine shroud. Clean up all the dust and grime around the cylinder so that none of it can fall into the crankcase when it's open, and then pull the cylinder.

If the cylinder bore just has a bunch of aluminum deposits smeared on it then there's a good chance you'll be able to clean it up and re-use it, which would be good because the OEM cylinder is significantly better than your aftermarket options and new OEM is expensive. If there are deep vertical scratches cut into the cylinder plating then it's junk.

While it's apart, you should see how the main crank bearings feel, and look closely at the large-end connecting rod bearing. If any of those are bad then the job becomes a lot bigger, because a bad main crank bearing means total disassembly, including splitting the case, and a bad connecting rod bearing means a new crankshaft. Chances are good, though, that the bearings are fine.

Replacing the piston and cylinder is pretty straightforward. You should use a new wrist pin needle bearing and a new base gasket. Ideally you should torque the cylinder bolts to spec, but not everyone has a small torque wrench so a lot of saws get rebuilt by feel, and they usually survive. You should also then vac and/or pressure-test the motor before putting everything back together, but again, not everyone does that.

 

[NCFord]

I got the engine shroud, carburetor, and air box off. I just need to remove the head, which I will try to do soon.
On top of the fuel tank there is a fuel line with a spring type thing inside it. It that just the vent? It basically fell apart when I was working on it.
It is just to the left of the off-run-halfchoke-choke lever.
I need to add that to my list of parts to order.

 

[Jon1270]

Yep, old-style tank vent.

 

[Jags]

Don't be afraid to take plenty of pictures during disassembly. All those little "oh - I will remember that..." moments...

 

[NCFord]

I guess I need to buy a long skinny torx-27 for the head bolts, unless there is some other trick. Everything I have is a socket type or just too fat to fit through the
opening in the cooling fins.

 

[Oldman47]

I don't know if it is a T-27 but my 026 came with 2 tools, a torx and one of those combination screw drive and bar wrench things. The torx also is used for my muffler mounting.

 

[Jon1270]

Your Stihl dealer will have an L-shaped T-27 driver available for cheap that will do the trick; an my local dealer they're $1. I ended up buying a 6" hex-drive bit that I can chuck in a rechargeable drill or use with a ratchet or torque wrench in combination with a 1/4" socket.

 

[TreePointer]

T-handle drivers are my go-to tools for chainsaws and other OPE. Cylinder bolts are often so difficult (tight or as a result of thread locking compound) that a regular/straight handle won't give you enough torque to get it started. The T-handle also is more likely than a than a ratchet or L-handle to spin the fastener/bolt straight and keep its work end inside the fastener head.

Be careful when using a T-handle when reattaching parts. They can generate a lot more torque than a straight screwdriver (I've broken a cylinder bolt with one). When reattaching cylinders, I use a 6" bit in a torque wrench as Jon1270 mentioned.

If you plan on making a habit of rehabilitating chainsaws, consider investing in a set:
http://www.baileysonline.com/Tools-...Torx/Complete-Set-of-Wiha-Chain-Saw-Tools.axd

 

[NCFord]

Ok. I got the head off and the piston looks shot. In side the cylinder looks pretty good, no scoring or anything. What is the best way to get the piston off? It is a bit tight but does move. How do you get the spring type ring off each end of the wrist pin? I think the piston has the 10 mm wrist pin, but will check it with a micrometer when I get it off, much easier then looking up serials numbers. The main bearing seem fine as well as the large end connecting rood bearing. The large connecting rood bearing does move from side to side a bit, but zero when moved up or down.(in the direction of the piston) so I think that is good.

 

[Jon1270]

Sounds like things are looking good. If the fins on top of the cylinder are diagonal then it's probably (but not definitely) a 10mm model. There's a little indented area next to the pin clip where you can get a sharp tool, like an awl, behind the clip to lever it in and out. Once one of the clips is out you can use a punch to tap on the far side of the pin and push it out of the piston. Be careful to prop the piston up on something while doing this so that the tapping impacts don't put stress on the connecting rod or its bearings.

If you look around you'll find a lot of recommendations for Meteor pistons, but Stihl has recently dropped its prices on many pistons so you might want to go for the real McCoy instead of aftermarket. You'll also need a wrist pin bearing and a base gasket.

Is the piston scoring concentrated on the exhaust side, or is it all the way around?

 

[NCFord]

Yes the piston scoring is concentrated on the exhaust side. the intake side does not look bad at all.
I tried to post pics last night but it did not work.

I am going to order a new piston, wrist pin and bearing and base gasket. I also measured the outside of the wrist pin and it
is 12mm.

 

[NCFord]

Anyone have a favorite site for stihl parts? I have been looking for awhile and most of what I find is aftermarket stuff from china. Some of it seems like a good deal but I have not had great luck with cheap parts lately.

 

[NCFord]

(broken link removed to http://www.ebay.com/itm/50MM-Piston-With-Ring-Gasket-Pin-Bearing-For-STIHL-Chainsaw-044-MS440-NEW-12MM-/290964766585?pt=LH_DefaultDomain_0&hash=item43bed9ff79)

How is that possible? I mean $12.50 for a piston and everything including shipping...from Hong Kong no less. The shipping must cost more than that. Not my choice.

 

[Jon1270]

Yes the piston scoring is concentrated on the exhaust side. the intake side does not look bad at all.

If you're not absolutely sure it was straight gassed, you'd better do a pressure/vac test after reassembling it. You really should do it in any case, but if you're unsure of the cause of the original problem then you should REALLY REALLY do the tests to ensure that you won't blow up the motor again after 15 minutes of runtime.

I would not risk one of those super-cheap pistons, it's not unheard of for them to break. OEM is best. Meteor is good. Espian is good.

 

[NCFord]

I do believe that it was straight gassed. After looking at the cylinder more carefully, it looks and feels like there are some scratches on the exhaust side, so I'm going to replace the cylinder as well. I might get the meteor cylinder and piston, but I would like to price the stihl parts as well. It does not appear that stihl sells parts online which means I have to go to a dealer. That's great since there is a stihl across the street from my house but I don't think they will even know what a piston is. It's in a ACE hardware store and they don't see know a lot about saws, but I will check anyways.

 

[claydogg84]

I do believe that it was straight gassed. After looking at the cylinder more carefully, it looks and feels like there are some scratches on the exhaust side, so I'm going to replace the cylinder as well. I might get the meteor cylinder and piston, but I would like to price the stihl parts as well. It does not appear that stihl sells parts online which means I have to go to a dealer. That's great since there is a stihl across the street from my house but I don't think they will even know what a piston is. It's in a ACE hardware store and they don't see know a lot about saws, but I will check anyways.

I believe you can get Stihl parts online @ baileysonline.com

 

[NCFord]

I have ordered all the parts and they will be here soon, but I have a question about the exhaust. It is completely hollow inside. Is there suppose to be any baffles or anything?

 

[Jon1270]

It is completely hollow inside.

Normal, in some of them at least.

 

[NCFord]

i am just getting around to install on my new parts for the 044 and was wondering what is the proper cyclinder bolt torque? I do have a torque wrench that goes down to
10 ft-pounds.

 

[Jon1270]

i am just getting around to install on my new parts for the 044 and was wondering what is the proper cyclinder bolt torque? I do have a torque wrench that goes down to
10 ft-pounds.

That wrench won't do it. The spec for the MS440, which is the closest I could dig up, is 8.5 foot pounds / 11.5 Nm.

Edited to add: found the 044 spec, which is the same as the 440.

 

[NCFord]

thanks, I might have to "guess" a little I suppose. I think a lot of folks do he same thing with that low of a torque.

 

[Jon1270]

Yeah, I'm sure that's very common. Last year I picked up a nice 1/4" drive torque wrench that tops out at 200 inch-pounds and takes the guesswork out of it, but it's definitely a specialty tool.