Having swopped diffs and bearings in my gearbox it got me thinking.....

One diff bearing (race) is fixed and the other is installed so as to be able to move slightly. This is held against the bearing itself by a spring washer and/or shim arrangement.

Having installed the diff I thought i would close the box to see if all was good but when tightened down the diff seems a little tight to turn. I know there was no gasket present but this got me thinking as to how tight the diff should be. A chat with the local Ford dealer and it would seem all that is available is a series of thin shims, 0.06mm, then 0.1mm and up in 0.1mm incraments.

So is there a way to determin the loading on the diff bearings and hence work out what thickness of shim is required???

Seems older box's use a spring washer arrangement...

Cheers

marvin

 

Hi mate, i remember asking my self the same question when i rebuilt mine, in the end i decided to go with the standard washers as long as the bearing are properly pressed into the case (giving the same height) and you are using the same diff and casing there isn't a lot else to change IMO.

From what i know you dont want any end float, the spring washers give pre load to minimise/eliminate end float. I would be concerned if you could move the diff in and out, and less so if the diff seems a little stiff. How stiff is stiff?

Any how, mines spot on so far.

Rob,

 

Thanks for the info,

Was really stiff but now seems ok and when I tighten the two halves of the box can hear the spring washers "groan" as they are squashed flat!


Am using the original box but with the diff from an RST, swopped one bearing and race from teh other box (save removing it from teh diff) and the other end is a new bearing and race so probably some difference, now cant get it to select reverse! So have to take it all apart again, probably something silly overlooked.

Did you use the moly paste during reassembly???

Cheers

marvin

 

I didn't use moly paste as i don't think its necessary with the box, unlike an engine rebuild.

The reverse selector can be a bit of a pain to get in the right place on the selector shaft from what i remember, theres definitely a knack to reassembling the box, i found a second set of hands very hands, to guide things in.

I may have some pics somwhere if you need them?

Rob,

 

Well can get 1 to 5, a bit stiff but then no oil in the box etc....

Have the selector shaft rotated clockwise like it says but seems that the reverse gear is not pulled in to the mesh properly, am gona take it apart (not fully gasketed up any way) and try again, but am happy that I can get teh rest of it all correct!!

I note in a diagram I have it shows a spring under the selector shaft...was no spring in mine or is that one of the difference between 4 and 5 speed?

 

the spring under the shaft is only in the 4 speed.

 

Thanks for the info....

Well it all seems to work on a dry run on the bench.

Think the knack is to assemble the two halves of the box with it in reverse and the pin on the selector shaft (rotated fully clockwaise) correctly located in the lever that actuates reverse.

Also need the two large "C" Clips in place between the middle section housing and 5th gear housing - holds the lay and main shaft in the correct place allowing the selector mechanism less drag to totate on the slector forks.

So now to assemble with gaskets etc......!!

Marvin

 

Well done mate, theres certainly a knack to it! i think i assembled the cassette and selector out of the box and got some to guide it in.

Robm