Stihl 044.

[BrettS]

So I have bought another saw, a Stihl 044.
The p/o said "It has only just had new barrel and piston kit, new rubber fuel pipe and crankcase breather pipes, new rubber carb manifold fitting, new spark plug,
The saw was running great for about 2 hours then it stopped.
I was able to still turn it over with the pull start afterwards but it would not start again
It has now jammed when trying to pull start it earlier today and it wont turn over now".
Have pulled it down, seems a piston pin circlip come adrift and smashed up the insides.
The piston is toast, cylinder (50mm) is marginal, crank bearings are shot and the clutch side of the crankshaft has a wobble.
Am thinking it is hybrid time.
There is so many options for this saw that I am confused, the saw is the early 10mm pin so what I am fixing to do is to split the case and replace the crank for a straight 12mm pin crank then a 046 cyl/piston with new bearings/seals from a local bearing supply house, replace the muffler cover with a 046 dual port cover. Can the 10mm crank be replaced for a 12mm crank?, is there anything special I need to know about the bearings/seals, eg when I rebuilt the 260, one bearing had the seal attached.
Been doing a lot of reading about cyl swaps, from what I read it seems the 52mm 046 cyl on a 044 (12mm pin) bottom end is the way to go.
What is the difference between the 52mm 046 cyl and the 52mm "big bore" 044 cyl?.
I am quite happy porting the cylinder if need be as well as squish/compression adjustment etc as I did with the 260.
Cheers all.

.

 

[pioneerguy600]

The crank can be swapped in but make sure the crank throws will clear the bottom of the crankcase, sometimes it needs some work to get clearance. The OEM 046 cylinder is the better choice over the BB kit.

 

[Brian Carlson]

Will have to adjust the cylinder mounting holes because the 046 uses larger bolts and a larger bolt pattern on the cylinder. I know the clutch side bearings are different between the 034 and the 046 but have never measured the crank journals to do a swap. I would just find a later ms440 crank with the 12mm pin and then put the 046 cylinder on it.

 

[BrettS]

Have had a closer look at the saw......the cylinder has some scoring but only on the middle of the transfer bridges and on the bottom lip of the inlet port, four lines on one bridge and one line on the other. The ridges do catch a finger nail and I have rubbed them down with some sandpaper and they are much smoother.
I have cleaned up worse back when I used to work in a small engine shop.
I thought the bearings were shot as they kept jamming but it turned out that the remains of the piston pin circlip was still in the crankcase and was jamming the crank, took that out and now the crank spins freely.
The clutch side crank wobble was a non event, it turned out (I think?) that someone didn't fit the notch to the oil pump drive and as the clutch bearing is plastic the clutch bell was wobbling.
The flywheel has a very slight wobble though.
Hmm what to do, put a piston kit in the saw as it sits or split the case (not what I want to do) and fit a 12mm pin crank with 046 cyl/piston.

 

[Brian Carlson]

I would get a piston kit and clean everything up for reassembly. It will still run good. Just make sure the squish is right and you will be cutting in no time. I would just slap a meteor kit in it.