GolfGTIforum.co.uk

General => The garage => Topic started by: richandhazel on 11 September 2003, 16:12

Title: Gearbox rebuild
Post by: richandhazel on 11 September 2003, 16:12
Some of you may remember a while back (before I had the problem with my Audi driveshaft coupling snapping) I was talking about dismantling my worst (and completely knackered) Mk1 gearbox and seeing how easy/difficult it is to fix DIY.
As its a miserable day and I have finally cleared out the garage I have decided to give it a go.
Pictures and details to follow...........
Title: Re:Gearbox rebuild
Post by: golfvr6 on 11 September 2003, 16:49
Yep i remember, keep us posted  ;)
Title: Re:Gearbox rebuild
Post by: richandhazel on 11 September 2003, 17:59
Going OK so far. All the 5th gear assy is now removed. I now need to buy some more spline drive bits as I only have 8 and 12mm and it appears I now need a 5mm one!
Title: Re:Gearbox rebuild
Post by: golfvr6 on 11 September 2003, 20:42
How do separate the gearbox housing from the diff/clutch housing? couldn't get my one apart  :'(
Title: Re:Gearbox rebuild
Post by: richandhazel on 12 September 2003, 03:03
I'll let you know how I get on............haven't got that far yet.
Title: Re:Gearbox rebuild
Post by: richandhazel on 12 September 2003, 13:48
Bought a complete spline set this morning.
Housings are now seperated. It was no problem at all. I looked at the special VW puller and made one out of some steel box section I had kicking around..........I'll post all the info and pics soon.
Have now removed the selector forks and am moving onto removing the gears and mainshaft etc.
I'm enjoying this, not nearly as difficult as I was expecting...........so far.


How do separate the gearbox housing from the diff/clutch housing? couldn't get my one apart  :'(
Title: Re:Gearbox rebuild
Post by: golfvr6 on 12 September 2003, 15:34
I removed all the bolts on mine , but the 2 section won't separate  >:(
Title: Re:Gearbox rebuild
Post by: richandhazel on 12 September 2003, 15:40
Once I got the puller on, I wound it in a little and simply tapped all round the housing joint with non metallic hammer.........just popped apart. Maybe I got lucky  :-\
Title: Re:Gearbox rebuild
Post by: golfvr6 on 12 September 2003, 16:09
Do you have to remove the input shaft bearing to get the cases apart, or just undo all the bolts around the outside or the gearbox section  ???
Title: Re:Gearbox rebuild
Post by: richandhazel on 12 September 2003, 20:03
There is a clamping plate that holds the mainshaft bearing in position. (Item 14 page 152 of the Haynes manual 726, the brown one). That was what I needed the m6 12 point spline drive for last night. Undo the 4 screws (item 10) and then all the bolts around the outside of the gearbox casing.

Mine is now completely dissassembled and I now know what has happened to the gearbox. The pinion shaft lower bearing has broken up and parts of the bearing have found their way between the diff and the lower pinion diff drive causing major damage to both. Parts of the bearing have also found their way into the 5th gear assy and caused major damage to that.
Photo's and a full write up to follow..........for anyone thats interested.  
Title: Re:Gearbox rebuild
Post by: tinman on 12 September 2003, 22:24
errm , any chance of rebuilding my gearbox when your done ;-)

its not broken, it just needs TLC.

Tinman
Title: Re:Gearbox rebuild
Post by: golfvr6 on 13 September 2003, 00:24
Let me guess 2nd gear synchromesh?  ;)
Title: Re:Gearbox rebuild
Post by: richandhazel on 13 September 2003, 12:26
The main reason I did this was to learn how to replace the second gear synchromesh........the most common failure of these boxes.
Title: Re:Gearbox rebuild
Post by: golfvr6 on 13 September 2003, 14:44
I never driven an old vw without this problem  >:(
Title: Re:Gearbox rebuild
Post by: tinman on 13 September 2003, 17:58
Let me guess 2nd gear synchromesh?  ;)

don't think so. excess sound coming from it definitely, and third is becoming not so much tricky to get into but you do need a fair degree of accuracy. after 158,000 its on my list of things to look at in stage 3.

Regards,
Tinman
Title: Re:Gearbox rebuild
Post by: golfvr6 on 14 September 2003, 17:52
Maybe the gearshift rod adjustment is slighty out?
Title: Re:Gearbox rebuild
Post by: MK1_BOY on 18 September 2003, 12:59
Where are the pics then Rich.... :-\
Title: Re:Gearbox rebuild
Post by: richandhazel on 18 September 2003, 13:07
Still working on the write up but I have made a start:-

http://homepage.ntlworld.com/richandhazel1/gti/profix1/gearbox/files/main.htm

Title: Re:Gearbox rebuild
Post by: golfvr6 on 18 September 2003, 14:54
I'll have a look later when i get a chance  ;)
Title: Re:Gearbox rebuild
Post by: adyh on 19 September 2003, 10:57
Great pictures of your fifth gear .... clutch down !!!!
Title: Re:Gearbox rebuild
Post by: richandhazel on 19 September 2003, 11:10
You wait until you see the diff and lower pinion and bearing! Not good  :'(
Title: Re:Gearbox rebuild
Post by: MK1_BOY on 28 September 2003, 19:11
I've seen it in the metal, its pretty impressive guys....  So simple...  This man can teach you allot...