R72 Gearbox Output Shaft Bearing Removal

Hi,

I am well underway on rebuilding the gearbox but I have one question and want to clarify the Bigjimny wiki article on the rebuild. I have replaced all the bearings but the ones on the output shaft.



The screen print from the wiki page shows the shaft and bearing in question. If I have it right the top bearing (already removed in picture), gear and bottom bearing all come of the top of the shaft one after another?

Just want to double check as its not very obvious looking at the shaft.

Thanks Sam

Yup, they all gotta go to get to the bearing.

Thanks, your help is appreciated!

All of the bearings have now been replaced and the gearbox is now being put back together. Rebuilding the box was far easier than taking the engine/gearbox out! All this because of one knackered bearing.

Will post some photos on my build thread.

Sam

Sorry to jump in on this thread but...

Does anyone know why the R72 box was prone to these bearings breaking up?

And does rebuilding with new and presumably different bearings necessarily mean that the bearings wont fail again?

Again, not meaning to hijack Zukracer's thread, but I thought that while on the subject it might be worth asking... :whistle:

Not 100% sure why they dont last, but i found 2 bearings with some noise/grinding in them when i did mine, both where on the countershaft. Maybe oil level related, or maybe directional force problems, i dont know. I just bought the car , with the issue allready.

The new bearings where all sealed, except for one..
Not sure if thats a good thing either, but the bearing kit seller sure ment it was better than stock.

If the new bearings lasts another 90k km, im good for 8-10 years or so.. Ive never owned a car for more than 4.

Max Headroom wrote: Sorry to jump in on this thread but...

Does anyone know why the R72 box was prone to these bearings breaking up?

And does rebuilding with new and presumably different bearings necessarily mean that the bearings wont fail again?

Again, not meaning to hijack Zukracer's thread, but I thought that while on the subject it might be worth asking... :whistle:

Max Headroom wrote: Sorry to jump in on this thread but...

Does anyone know why the R72 box was prone to these bearings breaking up?

And does rebuilding with new and presumably different bearings necessarily mean that the bearings wont fail again?

Again, not meaning to hijack Zukracer's thread, but I thought that while on the subject it might be worth asking... :whistle:

One reason is that more of the torque is being transfered in the gearbox in the R72 compared to older models with different gearing. More or less the difference in the torque and thus the load is the same as the difference in the gearing. This is also the reason why the 2005 and more recent jimnys do not have the problem with the transfer box as the load on it is less. Of course there is also the wider chain in the transfer cases from 2005 and up.
If you cannot change the bearing size to wider or bigger bearings there is not much you can do to make it any stronger.
Better lubrication, better cooling will help, using the correct oil viscosity as well. Higher revs will lower the torque, but higher revs could make it hotter and make lubrication worse.
Not sure how smart it is to change the bearings to closed ones though, but this has also been done to the SJ413/samurai gearbox on older Suzukis...