My 034 seems to have a deathwish.

A couple of the mods will remember this saw from back before this site existed. The first non-running saw I acquired was an 034 (free!) with a spun PTO-side crank bearing. The bearing was a sloppy fit in the case. Attempts to save the original case failed miserably, and the parts have sat in a tray for several months. I recently decided to have another crack at it. I found what looked (and was claimed to be) a crankcase with its own crankshaft and good, original bearings intact, in excellent shape on eBay. I bought it, and at first it seemed fine but when I was preparing to build the saw up on it I discovered that the rod bearing was shot. The seller apologized profusely and offered a full refund, but instead I suggested he just give me a partial refund. I figured I could split the case and substitute my original crank. The seller was fine with that plan.

When I split the case, the recoil-side bearing stayed on the crankshaft rather than in the case. I didn't think anything of it at the time. I decided to replace the bearings, so I ordered an aftermarket set and put the saw back on the shelf while I waited for them to arrive. They got here this morning, and I discovered to my dismay that the recoil-side bearing fits, just barely, into its recess without heating the case half. It's not a sloppy fit at all; in fact it's so tight that I didn't notice the slop until *after* I'd already heated the case, dropped in the bearing, and was playing with it after it all cooled. There had been a particle of debris or something in the new bearing that was occasionally catching as I spun the inner race, and I had been fiddling with it for several minutes trying to figure that out before I realized I could push the bearing out of the case by hand.

So, damm. What's worse is that I can't make sense of it. Unlike the original case with the horrificly spun PTO bearing, this one doesn't have any visible sign of having spun, i.e. no scratches or slop. It looks perfect, and there's so little play that I could easily have assembled the saw and not even noticed the problem. And yet the recess in the case is a couple of thousandths too big, and if you push in just the right way, the bearing will come out easily.

Can any of the more experienced mechanics offer a theory as to how this might happen? The crankshaft that I took out of this case was in really bad shape -- it actually fell apart when I split the case, because one of the counterweights had cracked at the rod journal, and both counterweights had the telltale rainbow of overheating colors near the rod journal. I couldn't see any evidence that the overheating had progressed along the crankshaft or affected the case. I can't help but think it's related somehow, but I can't figure out how.

 

I'm feeling for ya, sometimes you just can't win. I only split one case, an 031, and decided that I didn't want to ever go down that road again. Didn't have the right tools to do it right myself. Gambled and bought a used one on ebay that was nice. In retrospect, probably should have grabbed the full refund when you had the chance, and gone for another one, but that's downstream now. That's probably your cheapest "out" at this point still ................ roll the dice on another ebay case, versus the cost of new/used OEM parts bought individually to get the old case working.

Something like this one for $45 - ?

http://www.ebay.com/itm/STIHL-CHAIN...071?pt=LH_DefaultDomain_0&hash=item35cb54fbff

 

Thanks, Boog. I don't regret splitting the case. I improvised a tool for it and the process went pretty smoothly, partly because I had some practice last year when I split the first damaged case.

The fit of this bearing is so close that it's tempting to just use it, along with some of the appropriate (and expensive) green Loctite. Even as it is the bearing literally squeaks in and out -- there's no perceptible radial play whatsoever. *sigh*

 

Try the loctite and see if it holds. At this point you don't have much too lose.

 

Lucky, eh? This "free" project saw is already the most expensive one I've had so far. It has taught me a lot, though, so on balance it's still worth it.

 

Does the original bearing fit tightly?

 

Nope, it's just like the replacement.

 

I just can't stay away from a 1125 discussion on here haha. Since MasterMech helped me pull the trigger on my first 034, I've been into 7 1125 saws. Out of the 7 I have 5 runners. One of the cases is completely shot with a shot clutch-side bearing and damage from AV mounts. The bearing is crunchy and I bought it for parts after giving the crank a wiggle. The other case (036 I think) is rough looking but seems tight. I also know of another 034 or 036 that I could get pretty cheap for ya.
Dex- have you been down the 034/036 hybrid road yet? If so then you probably know the usual changes- probable cylinder cover mod, possible muffler spacers, etc. If you need any parts for the build let me know. Are you goin with aftermarket? My Hyway is a great running saw...

 

My Uncle told me years ago...that its always the "free" projects that always cost a fella the most . I have found this to always be true !