Author Topic: gearbox rebuild (Read 4275 times)

126dave · « **on:** November 23, 2006, 09:07:44 PM »

hi guys.....got my bits..and im gna start on my spare 'box soon.....seems an easy enough job,but,anyone on here done it already?,any cheats/pointers etc? :wink:

im still not sure about the idea of a bis driven plate in an aircooled clutch (bruce?)........ does it really fit ok?

also,im still after an aircooled bell housing.....must be one out there on a knackerd 'box?

as you can see im looking at a rebuilt (longer gearing) bis 'box with a/cooled bell housing and bis drivin plate to fit in my little buzz bomb :cool:

Chris Lakin · « **Reply #1 on:** November 23, 2006, 10:14:43 PM »

good luck Dave, i wish i could offer some advice, but i know nothing about gearboxs, one thing i do know about 126's boxes is that the 1st gear selector is prone to snapping, as i found out. I had been driving my BIS for a year without 1st gear, when i drained the oil this came out,

(i belive this is from the 1st gear selector fork)

Is it possible to stregnthen this? or will lots of good oil changed help keep the etal healthy?

just somthing to consider maybe as i think this is the flaw of the gearbox (everyone evenutaly loses 1st gear in a 126)

regards

Chris

126dave · « **Reply #2 on:** November 23, 2006, 10:27:29 PM »

thanks chris,the gearbox's are a little weak,but nothing bad about them,the reason im rebuilding the bis box is that it suffered catasrophic failiure aftr being given to a young lady to learn to drive in.......its out of the wreck in the yard.
i've just spent the best part of last weekend explaining to my girlfriend about 126 'boxes,with the bis one in bits on the bench with the shattered gears as evidence for my lecture!!

......only then did i let her drive mine.

reg oil changes and mechanical sympathey and they will last as long as you want them to.

Chris Lakin · « **Reply #3 on:** November 23, 2006, 10:59:15 PM »

hahaha that made laugh "how not to use a gearbox lecture 1"

i could just picture you with lights dimmed and a slide show running

youre right though, i think the only way to look after a gearbox is to know how it works and what you should and shouldnt do i,e no synchrmesh on 1st!

ive had always driven my BIS with the greatest of care, my first gear went after the clutch cable started to go, while travelling up to yorkshire in my BIS, it snapped when i got home (luckily) i replaced and adjusted cable accordingly then next day it just went. So i think clutch adjustments plays apart too.

Dave did you get your www.fiat126.co.uk sticker?

regards

Chris

Bruce · « **Reply #4 on:** November 24, 2006, 01:48:12 PM »

yes the bis clutch plate doies fit the aircooled clutch, mine lasted a lot longer after the "mod", and i've also rebuilt a 126 gearbox, when the 1st/reverse went on my deville i took the box out stripped it into its component parts, i then took the box from my spare jet black 126 and stripped that down also, i then sorted all the bits from the 2 boxes and built a box from the best. The pictures in the hains manual for the aircooled 126, will be good enough guide it you need a bit of help putting it back together, you should be able to complete the whole job in an afternoon. I also, at the same time, removed the reverse light swith and wiring and put it in my deville allong with the ltd edition rear lights.

Not sure how you intend to get the box out, but when i did mine i took the engine out to give me working space, removed the gear box leaving the bell housing and final drive in place. I had no pit or lifting gear, not even ramps, just an old scateboard to move the engine on.

126dave · « **Reply #5 on:** November 24, 2006, 06:07:27 PM »

thanks for the input guys,bruce,im gna pull the engine out then take the box out complete.......i want to keep mine as a spare,the bis box is already out and partialy in bits,thats why i want an a/cooled bell housing,so i can build this up fully spray painted and just fit it one day....gna be january now as im off in two weeks

the plan is to try the taller gearing of the bis before i fit a five speed conversion in my original box(as hudson henry suggested) :cool:

thanks for the info on the bis clutch bruce.im gna go for that one...i like the idea of the spring cushion affect with my full bore gearchanges!!

yes chris--thanks........one on the rear screen.the other is going on the new light blue sun visor when fitted........also i must post some picks of my powder coated red mesh lower back panel some time.... :wink:

126dave · « **Reply #6 on:** December 03, 2006, 04:13:59 PM »

well chaps...spent an enjoyable few hours today,stripped and cleaned the bis box and fitted all the new gears etc....on the bench now waiting for the a/c bell housing.
this was my first 126/transaxle box build,dead easy,so dont dump any more boxes,get the repair kit and get it sorted!! :cool:

Chris Lakin · « **Reply #7 on:** December 03, 2006, 07:33:44 PM »

excellent dave did you get any pics?

Can we make a workshop diary manual? on HOW TO FIX YOUR GEARBOX?

regards

Chris

126dave · « **Reply #8 on:** December 03, 2006, 07:47:25 PM »

well chris,a half decent tool kit,a bench,some patience and a haynes manuel (dont undo the pinion shaft front bearing,not needed) with some systematic workmanship and a novice will be able to do it.....its so straight forward
just a repair kit, some common sense and gasket set needed

Chris Lakin · « **Reply #9 on:** December 03, 2006, 09:23:30 PM »

sounds great, but what happens if a large bit drop out like in pic above i posted? I think its the 1st gear selector, so does that come in the kit?

regards

Chris

126dave · « **Reply #10 on:** December 05, 2006, 05:13:17 PM »

no,the kit only allows for abuse of first and reverse..........for further parts you need to strip the box then order from gerstl.

for instance ive replaced the sintered bush on the input shaft,the main source of play and then leaks, then oil on clutch, then destroyed box mountings/first gear............................ :shock:

how a selector has been snapped is beyond me,total savegry i gues by a previous owner