044 rebuild, how difficult?

[trouts2]

How difficult is rebuilding an 044?

I have rebuilt many 7-10 hp Tecumseh L heads, a Yamaha L head and an MS180. The MS180 took a long time mostly because of having lots of trouble with the buffers. If I did one again it would be fairly easy. How is rebuilding an 044 that has been run with no oil? Is it much more difficult than the 180? Any special tools required?

For the 180 I took pictures for the disassembly sequence and wrote notes during disassembly. I put groups of parts in bags and numbered the bags. Part of the reason for doing that was the disassembly was in the summer and I would not get back to it until after Christmas.

The 044 supposedly was owned by a homeowner and not used much. At one point he forget to put in oil in the gas and scored the cylinder. I can get it for $50 and thinking it might be a good project. I'm not a pro, just a light user of chainsaws. The 044 would be useful at times for ripping as it can take a long bar.
Any feedback would be appreciated.
David

 

[Jacob J.]

$50 for a complete 044 is an excellent buy. The difficulty of rebuilding one depends on how much work it needs.

Starting out, you'll need a standard scrench, T-27 wrench, small and medium flat head screw drivers, good needle nose pliers, a piston stop, a good deep well 19mm socket and ratchet, a seal puller (if you plan on doing the seals), 8mm nut driver, and a flywheel puller (among other tools).

Additional tools will be needed if you plan on splitting the crankcase.

 

[trouts2]

Jacob,
I have those tools except for the seal puller which I could get. ? Maybe Harbor Freight has puller. Just googled around about that and many suggest a screwdriver with a notch. Would that work on an 044?
I probably would want replace the crank bearings. Is that the item that causes the case to be split? Only for new bearings?
I've been googling around and think I can get a short block with a case fairly cheap but the postings are not so clear. It looks like they come in 50mm, 52mm and 54mm bore sizes. They show and engine sitting in the crank case for $150-$200 so I assume the crank bearings are inside the case. ? I guess you just add the parts from your saw like oiler, clutch, flywheel & etc. I'll google around the net for 044 rebuild videos.

 

[trouts2]

Found a video of a screwdriver puller. Seems like just a notch would work. Why is splitting the case hard? Are there lots of parts in the that are difficult to stuff back in?

 

[Jacob J.]

If you've never split the crankcase on a saw before, it can be challenging. It's more involved than a top end rebuild on a four-stroke engine.

I would stay away from those aftermarket short blocks- they're put together very cheaply with low-grade parts and have a high failure rate.

 

[Jacob J.]

https://www.arboristsite.com/community/threads/044-rebuild.309737/

https://www.arboristsite.com/community/threads/044-rebuild.257614/

 

[trouts2]

Jacob J,

Thanks for the rebuild links. The pictures and detail was very helpful. From the write ups it seems the major problem was getting tight fitting bearings out of the split cases. A few weeks ago I did a Honda 828 snowblower gearbox repair which had three bearings in an aluminum case that mounted to the side frame of the snowblower base. After getting it apart it presented a problem like the split cases of the Stihl 044 in the videos.

Two of the bearings only had small holes on the side so a punch like a socket would not work. The third bearing was covered by the case on one side so no way to push out that bearing either. I did not have inside bearing pullers but after poking around the net found that the case could be heated and the bearing “just fall out”.

I heated the case slowly with a heat gun but they would not budge. I tried a propane torch on the case only and that did not work. I then tried putting the case in a counter top oven for a more reliable way to apply heat. I started at 250 and worked up in 50 degree increments until I could get them to move a little. At 350 they did not “fall out” but they would finally move slightly like 1/32.

I have an L shaped small tool that has ends with miniature hammer claws on both ends. The metal is strong and the claw ends just thin enough to get a grab on the inside of the bearing bottom against the case. With the L side inside the bearing base I could just get enough grip to work around the inside of the bearing and inch them out. I also used the curve side of miniature channel locks which fit inside the bearing center. That had to be done wearing welding gloves but after lots of struggling all the bearings finally came out.

The snowblower was old, the grease dried up in the case and solidified in the bearing slots. There was some rust on the outside of the bearings making it impossible for them to “just fall out”.

All in all it took many hours to get them out but if I had to do that job again it would be “fairly easy”. It looks like the Stihl bearings are the same issue so I don’t think I’ll have a problem there.

I have some small pullers and have pulled a few chainsaw bearings off cranks. Hopefully those will work on the 044 if they are tough to get off.

Another issue is getting the flywheel off which can be a pain. I’ve taken of 4-5 chainsaw flywheels off and don’t like banging on the crank end but maybe I’ll get lucky with 044.

Maybe it is the flywheel and case bearings are the major problems. If that is the case then the other issue is getting it apart in the right order and remembering where everything goes for the reinstall. That part is a worry as I’ve only done a full rebuild on an MS180. I took pictures and notes during the breakdown for that and can do that during the 044 disassembly. They were very helpful on the getting it back together.

So maybe the issues other than flywheel and bearings are break parts, clutch stuff, oiler and things like that. What other things in there are tricky and cause problems?

I bought the saw yesterday and will give rebuilding it a shot. $50 so not a big deal and maybe I'll end up with an ok saw.
Looking in through the exhaust port the exhaust side of the piston is badly scored. The opposite wall had faint cross hatching but no score marks.

 

[bayard]

getting the bearings out is not to bad. a toaster oven works good. you can make a home made puller also.