G/Box side plates, Gaskets or Shims???

I've often heard of the gaskets on gearbox side plates (both inner & outer plates) reffered to as shims.

Are they there just to stop oil leaks, or do they actually adjust a clearance somewhere??



Matt.

Matt,
Seperate beasts. The covers have large O-rings to stop oil leaks, and between the covers and diff bearing races are metal shims to set backlash.

This is for manual IRS Type 1 gearboxes I am assuming.

Ctefeh

My mistake (and edited), as the guys below have said, gaskets are used on swing axle covers.

[ Edited on 31/12/2006 by ctefeh ]

[ Edited on 31/12/2006 by ctefeh ]

on swing axle gear boxes, the "paper" gaskets between the axle housing and diff cover adjust the endplay of the axle in the axle housing

dumone wrote:on swing axle gear boxes, the "paper" gaskets between the axle housing and diff cover adjust the endplay of the axle in the axle housing

They only set the end play of the axle tube, which should be as close to zero as possible. The plastic 'daisy' can wear in, a little, to take up any difference in the matching domes. The 'paper gaskets' eventually became 'plastic shims' as the seal was transfered to an O-ring placed in the retaining ring.

early 40hp swing axles were my main concern - should have made that clearer.

So, I take it that the end play measurement is not super critical requiring measuring tools other than your own "feel" for it.


Matt.

PJMS wrote:They only set the end play of the axle tube, which should be as close to zero as possible.

Yes, they are usually set by feel...definitely no play in the axle tube.
I do this by trial and error with a different number of gaskets,
until I get the tube to move but fairly firm.

As for the gaskets between the side cover and the gearbox case,
this should be done cautiously to maintain(attain) the correct backlash of the crownwheel and pinion.

Later trannys have no gaskets between the side cover and case(O ring),
but early 40hp trannys had a gasket.