13 replies to this topic

[adammini]

Hi all,



Im replacing my gearbox this week (have to get it done before I get it tuned up on thurs!) and ive just taken off the transfer gear housing and the idler gear has alot of wear.

The reason im replacing the gearbox is because there is a nasty graunching sound. I thought it was a bearing in the gearbox but..

The wear is in the end which sits into the transfer housing, it is ridged and rough. I will upload a pic once the camera has finished importing.

Does this mean the idler bearing has gone? It feels ok, but I was going to replace it anyway.


Also, it look like im in desperate need of a idler bearing, i think I have a spare, it has 37 teeth, same as the one out of my box. Will this be ok?
Are there any main differencess between a A+ 998 idler gear and a A+ 1275?



Thanks

Ad

[adammini]

Here we go:

[Sprocket]

Thats well FUBAR'd!!

You need to replace the whole gear and the bearings in both the gear case and the transfer case.

If the gear you have is the same tooth count and A+ then there is no reason it wont work., make sure you check the clearance of the thrust before you assemble it all back on the engine. Do this by installing the idler gear into the gearbox, install the trasfer case with the gasket you intend to use and then torque up the bolts to the specified torque. Using two feeler gauges, measure the clearance of the idler gear. If it is outside of the limits, obtain the correct thrust washers to rectify it or combination of different gaskets and thrust washers. If you dont, the idler gear will be noisy and the bearings will eventualy fail. Its one of the most important clearancies.

Also worth checking the primary gear end float as well and correcting that while your in there, again an important clearance

[adammini]

Thats well FUBAR'd!!

Yup, yes it is! I couldnt believe that damage. I very glad I stopped driving the mini when I did!

Thanks mini sprocket, all very useful stuff.

Now, the idler gear I have spare looks like it has been sat somewhere damp and one side where the bearing sits it has corroded. Not all over just on the outer end.
My dad has taken most of the rust off with very fine wet & dry with parifin, but when you run your nail over it, it still feels a little rough.

Shall I keep cutting it back untill its smooth or risk running it as it is or find a new idler gear pronto!



Cheers

Ad

[icklemini]

use some scotchbrite to clean up the gear - if this dont clean up the pits then get a replacement gear..

(any pics - as it may well be ok - depending on where the corrosion is..)

your original gear is knackered as MS has stated...

[adammini]

thanks icklemini, heres a pic of the worst of the corosion.

Its slightly pitted but not very much, I will give it a bit of a clean up and hope that removes the pits.

[icklemini]

hmmm - if it is at all pitted then get a replacement as if the surface isnt silky smooth then it'll go the same as the original.. :s

[adammini]

hmmm - if it is at all pitted then get a replacement as if the surface isnt silky smooth then it'll go the same as the original.. :s

Yea, if it isnt then I will be a tad nervous.
Ive just had the box off and it looks in great condition, so the problem was the idler gear! Doh!
At least I have a spare box with 25k under its belt!

So whats the likelyhood of buying a new helical 37 teeth idler from minispares........... 0.00000%?!!

[icklemini]

all A+ idlers are the same...

ouchy: http://www.minispare....aspx?pid=34003

TTFN,
dave

[Big_Adam]

Eeeh, damn thats an expensive part. I'll have a root round the garage for on if you like Adam. Be out of a 998 tho.

Edited by Big_Adam, 14 August 2007 - 12:22 AM.

[adammini]

crumms, that is expensive!

Thanks Adam, that would be useful.

So even the 998cc A+ idlers are the same? I have a 998 lump under my bench......


I am considering a new one, as I need it pronto and dont know the condition of the 998 one. Humm..

[[email protected]]

All the A+ idler gears are interchangeable, yes

[Guess-Works.com]

if you need one, i've literally got bucket loads

[adammini]

if you need one, i've literally got bucket loads

Thanks John, I might get a spare one from you if thats ok.

Sorry for the late reply, been very manic. The idler I have cleaned up quite nicely so was ok.

The engine is now in the car running sort of ok, except now it wont start very well! Its at the garage to be sorted because I leave for Germany on Thursday!
We might have to go in my girlfriends micra if the bl***y mini ist fixed.