Re: Gearbox Shims
Posted: Fri Oct 29, 2010 9:50 pm
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Gearbox Shims
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Re: Gearbox Shims
Posted: Fri Oct 29, 2010 9:54 pm
Give the gear cluster /tree a tap with a soft hammer as you do up the end plate bolts
Re: Gearbox Shims
Posted: Fri Oct 29, 2010 10:25 pm
The bearing does appear to protrude into the casing, the gears sit below the shaft, the oilseal hasn't snagged, I've now done this 5 times with the same result, bearing out tomorrow I think. If there are rogue bearings about you could guarantee that I'd get one
Re: Gearbox Shims
Posted: Fri Oct 29, 2010 10:32 pm
tbh i always use old ones as i have never had one go on me
Re: Gearbox Shims
Posted: Fri Oct 29, 2010 10:34 pm
Ditto...mark wrote:tbh i always use old ones as i have never had one go on me
I've worn out a few but never had one fail...
Re: Gearbox Shims
Posted: Fri Oct 29, 2010 11:39 pm
It's an age thing Daddio
Re: Gearbox Shims
Posted: Sat Oct 30, 2010 1:06 pm
Fitted the old bearing (which didn't sound or feel any different to the new one) pulled the shaft in, 2mm shim , 6 thou clearance. Looking at the bearings side by side there was nothing that really stood out as different. Once again thanks for your replies
Re: Gearbox Shims
Posted: Sat Oct 30, 2010 4:20 pm
Glad you found it.
There are to things that can be done to make shimming a lot easier and quicker. Leave out the mainshaft and dowels when doing this,it is not neccessary for them to be there when shimming and and they just make the job of removing the endplate difficult. Fit them after you have it shimmed. Secondly, and I am standing by with a bucket of water for the flamers
, you do not need to torque the axle nut to hub torque specs. to set the shimming up. The 120lb torque is to lock the cone to the hub. When the cone is hard against the bearing(with washer underneath) with, say, 40lbs of torque, no amount of tightening is going to pull the axle any further in, it can't go any further, so all you will be doing is effectively stretching the hub nut threads. Of course, you will need some type of spacer to do this( a buggered up old cone works well).
Who ever made and sent out those dodgy hub bearing needs to learn how to use a micrometer and then be shot.
There are to things that can be done to make shimming a lot easier and quicker. Leave out the mainshaft and dowels when doing this,it is not neccessary for them to be there when shimming and and they just make the job of removing the endplate difficult. Fit them after you have it shimmed. Secondly, and I am standing by with a bucket of water for the flamers
, you do not need to torque the axle nut to hub torque specs. to set the shimming up. The 120lb torque is to lock the cone to the hub. When the cone is hard against the bearing(with washer underneath) with, say, 40lbs of torque, no amount of tightening is going to pull the axle any further in, it can't go any further, so all you will be doing is effectively stretching the hub nut threads. Of course, you will need some type of spacer to do this( a buggered up old cone works well).Who ever made and sent out those dodgy hub bearing needs to learn how to use a micrometer and then be shot.