18 replies to this topic

[1984mini25]

Hi all, i have just split my 998 engine to inspect the gearbox as it sounded as if i had straight cut gears or straight cut drops.

The wining noise will more than likely be down to the 3rd motion double roller bearing, not really a good sign as it only a matter of time before it fails and lakes half the box with it.

Although to fix/replace it you have to strip the guts completely out of the box.

[1977 Loud_Mini]

Ok thanks for all your help, so it makes sense really to rebuild the gearbox depending onwhich one i decide to choose, do i need a machine shop to press fit the bearing or can it be done at home? I think i've seen a topic on here which shows how to rebuild a gearbox.

Evan.

[1984mini25]

You can rebuild it your self with a few basic tools and sockets, the bearings just drift out.

The hardest part i found with mine was undoing the 2 big nuts. But after jamming the gearbox by selecting 2 gears at the same time and sliding the box under the mini, they weren't too hard the undo/tourqe back up.

[1977 Loud_Mini]

Thats good to hear, yeah i've heard about selecting 2 gears, 2nd and 4th and possibly reverse?

Just checked the tooth count on the 1275 box for the final drive and its 18 on the pinion and 62 on the crown wheel so that equates to 3.44 final drive as you guess-works rightly pointed out, will check the 998 tomorrow.
With the 296 camshaft i don't think i'd be wanting a 2.9 final drive (if thats what it is) but maybe the 3.44. I remember when driving the 998 it didn't have much top end as it was screaming rpm's wise.