Club126UK

Fiat 126 Chat => Fiat 126 Mechanical Problem Solving => Topic started by: barkingwilhelmina on May 18, 2011, 08:31:16 PM

Title: Gearbox woes!
Post by: barkingwilhelmina on May 18, 2011, 08:31:16 PM

Hello all, please help!.... I have recently installed a reconditioned gearbox into my 126. I ordered a gearbox without drive shafts, as I had a set out of another car I had a few years ago and they seemed in good condition. I installed these and put everything back as I found it.....Now when I drive the car there is definate play in the transmission which leads to an annoying un-even drive (almost a rocking back and forth). Changing up through the box is okay, but when you change back down (4th to 3rd and 3rd to 2nd) and let the clutch out you get a loud knocking from the back?

All mounts and rubbers are new
Everything is bolted up tight
All springs and clips are in place
Clutch is new

I have seen a gearbox man today who thinks it is the drive shaft splines, but I checked these when installing and they looked good? He wants to replace drive shafts and everything associated, engine mounts and linkage ......

Anyone have any ideas ???

Title: Re: Gearbox woes!
Post by: GTMaster on May 18, 2011, 09:54:37 PM

Hi,

When fitting the gearbox did you put grease onto the end of the input shaft (the bit that goes into the end of the crankshaft)? When ungreased, it can cause similar problems ('rough' clutch, slight shuddering and knocking sounds when depressing the clutch). Best to use graphite grease. Also good to lightly grease the input shaft where the clutch moves on (splines).

Title: Re: Gearbox woes!
Post by: Pete126 on May 18, 2011, 10:30:36 PM

All so check the rubber drive shaft coupling, the splines will look O.K. but the rubber perishes and may be coming away from the housing, did you put the anti-rattle springs in the end of the drive shafts.

Title: Re: Gearbox woes!
Post by: barkingwilhelmina on May 18, 2011, 10:51:54 PM

rubber drive shaft coupling... explain more, i cant picture this....? sounds promising though .......

Title: Re: Gearbox woes!
Post by: barkingwilhelmina on May 18, 2011, 11:10:24 PM

i just figured out what you mean, didn't realise they are rubber inside. you might be on to something

Title: Re: Gearbox woes!
Post by: Pete126 on May 18, 2011, 11:11:13 PM

 ;D

Title: Re: Gearbox woes!
Post by: thepuddlejumper on May 19, 2011, 01:13:26 PM

Did you check the backlash on the crownwheel and pinion and adjust if required as excessive play can cause similar problems

Title: Re: Gearbox woes!
Post by: barkingwilhelmina on May 19, 2011, 06:44:13 PM

How do you check the backlash and can it be done in situe....?

Title: Re: Gearbox woes!
Post by: thepuddlejumper on May 19, 2011, 09:18:16 PM

I am sure the gearbox needs to be out of the car as a dial gauge has to be inserted to mesure the float.  It is a bit complex to describe here, do you have a workshop manual if not there is a copy in the subscribers section.

Ralph