090AV Crank shim question

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Metallichg

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I have an early 090AV that I am rebuilding. had a broken Rod bearing, the early 2pc roller bearing on the connecting rod with 2 socket head Cap screws. I installed new crank bearings and seals. I made the case and gasket surfaces ultra clean. I reinstalled the crank and there were 2 felt shims (one on each side of the crank) inside the crank case. The case is together and torqued. My question is now that the crankcase is together, the crank spins hard. I need the flywheel to get enough Mechanical advantage to make it rotate. it looks like oil is oozing from the felt shims. Is this normal with this type of saw and "felt" shims-is it likely to turn easy if the felt shims get deformed to this size if I wait a few weeks, or did I do something wrong and need to pull it apart again? I didn't see anything in the manual about "felt" crank shims. thanks for any tips-JoeIMG_20170409_1338155.jpg
 
I'll be interested to see what others have to say here. I've had a few 090s apart and none of them had felt shims. Seems like an odd material to use in a crankcase too. I've rebuilt a couple of Contras as well, and one of them (but not the other) did have shims on the outsides of the crank, but they weren't felt - best I could tell they were Garolite or something like that. That particular crankcase also had what appeared to be factory machining to account for the shims (or, as I referred to them, thrust washers).

Just to be clear, you put it back together exactly as it had been? The crank bearing sleeves were installed the same and everything? Did you use a new OEM case gasket?
 
I used new outer races for the crank bearings. I did not use an OEM case gasket. The gasket I used looked a few thousandths thicker than the original, but the original email had that black tar gasket sealer on it. I coated my chinese gasket with that same stuff and re-assembled. I agree-felt seems very strange, but that is what came out when I took it apart. you can see them in the photo if you look close. it had roughly .015 end play and more run-out -enough to feel a jiggle which is why I opted for new bearings. I was going to replace the crank if the it still felt sloppy with the new bearings, but it seems to not move radially at all, and being tight, right now there is zero end play. Thanks-Joe
 
As far as your concern with the crank being hard to turn;

When putting cases back together with new bearings/seals I've never had a crank turn as easy as when I turned it before disassembly with the cylinder off. A couple times I've thought they were too hard and something was wrong, and the next day I come back and it's a bit easier. Basically, I believe that when it runs and heats up, the surfaces "get to know each other" and the crank becomes easier to turn.

I've never done an old Stihl, but assuming you did it right (others will help you out here) with the correct parts and such, I wouldn't worry about it as long as the bearings don't "catch" or "grab" when rotating the crank. They should be smooth and the amount of force needed to turn the crank should remain the same all 360 degrees.
 
Thanks-yes it does remain the same and does not feel like Grinding metal. I will do what you suggest and leave it all zippered up, maybe tomorrow it will be easier to turn over with the flywheel. I did use the Stickey purple assembly lube so the bearings are not dry. Thanks again-Joe
 
So, I had been out of town and got back this evening. This whole felt washer thing was bothering me. I have three 090s and an 070 in my shop with the top ends removed. I peeked inside, and all four of them have the washers. Based on a little poking with a pick, they're firmer than felt, like the Garolite I referenced above. They're thin, more like the one on the flywheel side in your photo as opposed to the thick one on the PTO side. Then I came back in and looked at mediaCAT and it does in fact show that part. The official name is "check ring", and the Stihl part number is 1106 036 9000. They're still available new and the retail cost here in my area from Bryan Equipment is $1.99.

This is just a theory, but I can't help but wonder if something caused your check rings to de-laminate or swell which thickened and softened them and is giving you the interference fit and making them seem like felt?

As easy as an 090 is to split I would opine that it would be worth the time and handful of dollars to put new check rings in. I would also be willing to bet with new check rings you'll have the free spinning crank you should have. I would also suggest while you're ordering the check rings go ahead and get a new OEM case gasket for an extra $1.29 (part number 1106 029 1210)!
 
The felt washers were applicable to the old-style crank that had the two-piece connecting rod that you mention/have. The felt washers are not used with the newer style crank because it is ever so slightly wider at the crank weights than the older cranks are. The theory behind the felt washers I believe was to collect and hold oil at those points because the main bearings are needle roller type instead of cassette ball-bearing type. I did the same exact thing about 20 years ago and did just what Beau is indicating- installed the new style check rings.
 
thank you for that. if it does not magically loosen up tomorrow, I will call the Stihl dealer and take your advice. the saw can't be so hard to turn over that I need a vise Grip to get leverage. thanks for the good advise-Joe
 
The felt washers were applicable to the old-style crank that had the two-piece connecting rod that you mention/have. The felt washers are not used with the newer style crank because it is ever so slightly wider at the crank weights than the older cranks are. The theory behind the felt washers I believe was to collect and hold oil at those points because the main bearings are needle roller type instead of cassette ball-bearing type. I did the same exact thing about 20 years ago and did just what Beau is indicating- installed the new style check rings.
that sums it up, I will post how it worked out when I get the new check rings. Thanks very much-Joe
 
After a mega long wait, the new check rings arrived today. they are plastic, not felt. attached is a photo of the old rings (one is over expanded) and the new plastic rings. Have not put it back together, but soon will. Here is what they look like and why my crank was so tight.IMG_20170428_1851569.jpg IMG_20170428_1851255.jpg
 

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Hey Guys,
came along this thread having the opposite problem:
While beeing sceptical about axial clearance and decomposition of the old rings over time, I installed the new type in my 070
from 1972, together with an OEM crankcase-seal. The bearings and crank-seals were kept.

zsfclehb.jpg



However, the axial celarance increased even more, now about 1.0 mm or 0.03'', far out of specs according to the old workshop manual (0.2-0.4 mm)!

whbddv87.jpg


Altough my rings were both made from the black type of plastic shown above (no felt), they were a bit thicker.
As written above, there is only one type of shims available today, 1106.036.9000.

So my questions are:

What happened to the saw of Metallchig ? And Jakob? Did it run in the end? What was the end play with the new-type-shims?
And when do you Guys start to worry about axial clearance of Stihl contra/070/090 ?
Last but not least, I messed up to remember the position of each bearing. Is this okay or
do I need to install new bearings with new racers now ?

best wishes,

Chris
 
I ended up using the plastic check rings. The crank turned over smoothly, so I finished the rebuild and it worked fine. My original felt check ring was bloated, causing loads of drag. The plastic seemed to be fine.
 
Hey Guys,
came along this thread having the opposite problem:
While beeing sceptical about axial clearance and decomposition of the old rings over time, I installed the new type in my 070
from 1972, together with an OEM crankcase-seal. The bearings and crank-seals were kept.

zsfclehb.jpg



However, the axial celarance increased even more, now about 1.0 mm or 0.03'', far out of specs according to the old workshop manual (0.2-0.4 mm)!

whbddv87.jpg


Altough my rings were both made from the black type of plastic shown above (no felt), they were a bit thicker.
As written above, there is only one type of shims available today, 1106.036.9000.

So my questions are:

What happened to the saw of Metallchig ? And Jakob? Did it run in the end? What was the end play with the new-type-shims?
And when do you Guys start to worry about axial clearance of Stihl contra/070/090 ?
Last but not least, I messed up to remember the position of each bearing. Is this okay or
do I need to install new bearings with new racers now ?

best wishes,

Chris

1mm is alot, are sure you're not missing out something? It wont do any harm but its better to double check everything
 
cannot find my thickness gauge. It was about .6mm and is now even larger, maybe but close to 1 mm.

I did not miss anything. Ordered a PTFE-rod today and will try to find someone with a lathe. o_O
 
took my thickness gauge back from home.

With the new washers, the axial play is between 0.6 and 0.65 mm

less than I estimated without that tool, more than I would like to have and probably out of specs.

damn, should just have left it as it was :omg:
 
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