Transfer case alignment

[1071 S]

(Quote) 1. ........., he'll explain that the transfer housing needs to match the gearbox case so that the idler gear and outrigger bearings are aligned properly

The best one to use is the one that came from the factory with the gearbox casing, but it's probably too late for that

2. (reply)1071 S wrote:
Soooo they line bored the the transfer case and gearbox case???? Never heard that before....

3. ( Further reply) Yeah I've heard of it, as a machinist, I'd like to see how they did it though! it's a blind hole, on the outside.
I reckon they had jigs, and they were interchangeable when built, but not 10 years later if you tried to mix fit older and recent ones. (Unquote)

I'd be interested to hear if anyone knows how BMC actually lined up the idler gear inner and outer bearing holes??? I suppose it must have some importance because they fitted alignment pins -

Am I just lucky that, never (sic) having worried about such alignment (other than sticking the pins in the holes) when swapping cases, I've not had any issues with the idler bearings?? My current setup is much nicer thanks to a friend with a full range of idler spacers/thrust washers (whatever they're called).

Cheers, Ian

[Spider]

The Transfer housings were not matched to any particular case, the major difference being pre-A+ and A+ as far as interchangeable goes, though, normally with the earlier cases one would (but not always!) keep the bigger idler gear bearing housings with the bigger gearcases.

The Transfer Housings are fairly precision doweled to the Gearcases and that's all that's relied upon for alignment of the Idler Gear and the Outrigger Bearings. Some are better than others though, but they are surprisingly pretty good.

[Spider]

Thread revival (while I was looking for something else)

This is the Factory's advice in regards to swapping / mixing / matching Transfer (Flywheel) Housings;-