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Iainip
25-11-2007, 10:54 AM
Hi again. this is just an update on the gearbox fault, which I hope may help other people. The car is now back on the road, the gearbox is fixed and is working normally. I had no information on the gearbox, but the only problems I had repairing it were finding out how the gear cluster came out of the housing, and how to get the drive shafts out of the diff. With the gearcase removed the cluster is held into the diff casing/bellhousing by 2 snap rings, 1 on each side of the front input shaft bearing in the bell housing. 1 is accessed behind the shaft seal housing and the other through the diff housing, easiest access with the diff out. To get the diff out the output flanges have to be pulled out, I did it carefully with 2 big pry bars, the shafts have a compressable retaining ring that stays on the shaft, and a ring of bolts takes the whole diff out. With the selector pivots and the detent mechanism removed, gearbox input shaft can be driven out with a copper mallet and the 2nd input shaft snap ring accessed and removed from the shaft as its pulled out and the, cluster and selectors come with it. Striping the shafts needs a standard saucer puller and is fairly straightforward. The box had broken up the 3rd gear syncro ring, got a new one from VAG £21.39, and rebuilt the box. No setting tools required if you don't remove any of the the taper roller bearings, except the one on the end of the output shaft, and there were no shims on it. Hope this helps somebody.

audimad
25-11-2007, 10:59 AM
WOW !! Unusual in this day'n age,someone stripping a 'box. Well done

Col
25-11-2007, 01:25 PM
Fantastic work.

I'll have a go at most things but wouldn't consider taking a gearbox apart.

gav.zilla
17-01-2008, 08:23 PM
hi ianip, looks like i'll be doing the same job soon!!
my '95 tdi is crunching going into 3rd too, i suspected the syncro and your problem has more or less confimed it!
have you had any further problems?
good info, thanks.

Iainip
19-01-2008, 12:04 PM
Hi gav.zilla, car has done about 2000 miles since the box was done and is running fine. I recently dropped the oil out of the box and there was quite a lot of fine brass contamination. It seems a bit much for it to be just "bedding in" of the new syncro ring, but I'm not meaning to do anything about it just now. Its got about 3000 miles to go until the next service is due and I'll drop the oil out the box again. My thoughts are that the car ran around for a while with no syncro, before it locked up, and maybe some slight damage that I didn't notice has been done to the gear the syncro ring enters, I've possibly missed some rough edges on the gear when I stripped the box, and it may be damaging the new syncro ring. I'm not to worried about it, as its only time to strip the box again if the need arises. its running fine and box is smooth and quiet. If your doing your box check the gear shape where the ring enters against a good one in the box, with a magnifying glass, and see that they look the same. If its any help I took a bunch of pictures of my box when it was in bits, but it would take while to send them, let me know if you want them.

gav.zilla
21-01-2008, 10:32 PM
great, thanks ianip, photos would be a big help if you wouldn't mind sending them.

gav.zilla
21-01-2008, 10:35 PM
i had to make another post in order to be able to pm you, as you need at least 5 posts. i'll pass my email on to you.
big thanks

Robbycroft
15-02-2008, 01:28 AM
"Hi Guys, I have a '99 T reg deisel A3, the gears crunch going from first to second and also clunk when going into reverse, this i can deal with. I can't deal with not being able to select fifth gear. The lever goes where it should but there is no fifth gear. Whats gone wrong here guys? My mates dad said he had the same problem on his Passat and a guy fixed it on the side of the road. Apparently there was a loose plate which needed screwing back down. Any ideas what this plate is? I will ask him for more detail and have a look myself, any info would be great."

Is my problem the same? I'd love to be able to fix it my self.

Iainip
16-02-2008, 10:55 AM
Sounds like the bolt you are talking about is in the linkage between the gearbox and the gear lever. If this comes loose or moves it can cause selection problems. The linkage is above the gearbox housing, and it may be a case of slackening the linkage, if its not already loose and repositioning it by trial and error until you get all the gears. I think there are a variety of linkages fitted to different models. If its not that, you are going to have to delve deeper.

gav.zilla
16-02-2008, 06:38 PM
thats the only roadside fix i think would be possible as there isn't much externally to adjust. i think that some boxes have that type of linkage, while others run a kind of push rod that runs concentrically within the input shaft and operates directly on the unconventional flywheel/clutch type assembly.
a friend at work has this set up on an octavia, he had some probs and while researching, he came across a common problem where a plate in the diff is rivetted in place with copper rivets, which can fail, leading to selection/drive probs. apparently there is a retrofit repair kit using ss rivets. many possibilities though, and the cheapest and easiest place to start would be linkage setup if applicable. definately worth a look

gav.zilla
16-02-2008, 06:45 PM
incidentally, my 'box rocks now! cheers ianip, sumthin about pics and a thousand words?!!
:beerchug: