Author Topic: HOW TO: Replace Drive Seals on Gearbox  (Read 15717 times)

Offline Agreeable Slick

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HOW TO: Replace Drive Seals on Gearbox
« on: 31 August 2005, 18:33 »
Right had afun doing this today only to find that it was the diff thats the problem, warrenting me getting a whole new gearbox etc. Anyhoo, i took pics of various stages throughout doing it.

Start off,

Remove both Wheels from the front axle and then turn so that the caliper is facing out of the wheel arch. and there is a pinch bolt that the ball joint from the suspension is held in with. Loosen that and drop the wishbone out from the pinch bracket.

Now follow the driveshaft from the wheel centre, to the flange on the gearbox, and there are about 6-7 torx bolts on there, holding the drive shaft in there. Looks like this.



Use the torx key to loosen them, its usually easier if someone is holding the brake disc to stop the shaft just rotating when you remove the torx bolts. The shaft will then drop off from the flange and is still attatched to the wheel hub. Get a 19mm socket and remove the hub nut. *caution have someone hold onto the drive shaft, as i nearly got cracked in the jewels when it came loose and swung out*

You should do the same on the other side then have two shafts looking like this.


This is the drivers side one, the passenge side one should be about 2/3 the length.

Then you should be presented with what looks like this:


this is the internal driveshaft, Consequently if there is any movement other than rotary on the shaft that has been exposed then it will mean that your bearings will be on the way out, much like mine, in which case it is usually cheaper to get a new gearbox rather than have it all stripped down and replaced.

When removing the seals from inside the shaft you have just exposed in above picture there is a special tool required for pulling the seal out, or you can make a bodge plate to use and pull it out. (special tool is reccommended) Once removed then get the new one and knock it into the position of the old one. Then all you need to do is the reverse of the above, takes about 2 hours all in all, thats without any hitches.

When re-fitting the driveshafts, then put the wheels on first and then nip up the driveshaft torx screws as the wheel on there will give an extra bit of pull, so the bolts can be done up nice and tight again.

Car back on the ground and seals are done. Remember to tighten your wheel nuts on the floor, common mistake.

Cheers all, will go hunting for my new transmission setup now.  :cry:
« Last Edit: 27 September 2005, 10:02 by Mk2GTI2.016v »

Offline eightvalve

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Re: How To: Replace Drive Seals on Gearbox
« Reply #1 on: 01 September 2005, 09:42 »
Very useful. I have done this too and would just add the following tips:
1.  Loosen the hub nuts before you even jack the car up. This will avoid injury later.
2.  You should be using a splined key on the drive shaft flange bolts as they are splined cap head screws (unless someone has changed yours for Torx)
3. I found the old seals came out quite easily using a large screw driver as a lever. Just ensure that the tip of the screw driver is barely catching th inside of the seal and this ensures that you wont score the inside seating face on the diff.
4.  When putting the new seals in, dont push them in all the way. If you inspect the old drive flanges, you will see that the seals have worn grooves into the flanges where they contact. If you put the new seals in the exact same spot they will be trying to seal on these worn grooves.  By leaving the new seals slightly proud (say 2mm) the sealing face will be contacting an un-worn part of the drive flange and will give a superior seal.
1989 Mk2 8v

Offline Gambit

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Re: How To: Replace Drive Seals on Gearbox
« Reply #2 on: 06 September 2005, 14:05 »
im in the gearbox club also :(

my diff rivets went last week, lucky though it decided to go when the car was stationary, so didnt end up with a rivet thru the casing!!

£250 though is getting it overhauled with the diff bolt kit fitted also

Offline PETEL

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Re: How To: Replace Drive Seals on Gearbox
« Reply #3 on: 06 September 2005, 19:22 »
You guys seem to be real experts at this !
However you have not mentioned how you replaced the driveshaft flange into the diff casing.
The back of the flange has a large coiled spring to pre-load the diff bearings presumably.
The drive flange has to be pressed in to allow the circlip to be replaced on the end of the diff shaft.
How did you do it ?

Offline Gambit

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Re: How To: Replace Drive Seals on Gearbox
« Reply #4 on: 06 September 2005, 20:09 »
nah i just used a block n hammer!! then the spring washer & circlip fitted and bobs your uncle!

Offline eightvalve

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Re: How To: Replace Drive Seals on Gearbox
« Reply #5 on: 07 September 2005, 11:01 »
You guys seem to be real experts at this !
However you have not mentioned how you replaced the driveshaft flange into the diff casing.
The back of the flange has a large coiled spring to pre-load the diff bearings presumably.
The drive flange has to be pressed in to allow the circlip to be replaced on the end of the diff shaft.
How did you do it ?


You'll notice the diff shaft is internally threaded.  This is for the problem you mentioned. There is a special tool you can use which screws into the drive shaft and then compresses the flange (and spring) in toward the gearbox which then lets you put the circlip in quite easily.  However, I did not have this tool. Instead, you can use a large cap head screw or hex bolt (I think its maybe M8 or M10 more probably). Screw the bolt part way into the shaft and then using a large flathead scew driver, use the head of the bolt to trap the tip of the screw driver and lever the flange in towards the gearbox, compressing the spring.  This gives you access to the circlip groove and your problem is sorted. 
1989 Mk2 8v

Offline Agreeable Slick

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Re: How To: Replace Drive Seals on Gearbox
« Reply #6 on: 07 September 2005, 17:16 »
M10 thread peeps. As 8v said, there is a special tool, but i just bodged my own together to push the spring back and then a big fook off crowbar to lever the old seal out and a nice sized screwdriver to get the new one avec circlip in.

Offline PETEL

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Re: How To: Replace Drive Seals on Gearbox
« Reply #7 on: 07 September 2005, 23:35 »

Thanks 8v but while you're levering on the shaft with one screwdriver its a bit difficult to use two more to get the plain circlip in !
If you don't have VW tool 201 you can make one as its the only sure way of doing this job properly & safely.
Yes M10 thread & it needs to be at least 8cm long.
Make a steel plate 10cm x 2cm x 4mm & drill a 10mm hole in the middle for the M10 thread to go through.
Grease the drive flange & carefully replace it on the diff shaft gently through the new oil seal.
Screw the M10 thread into the diff shaft, goes in abot 1cm.
Place the dished washer concave out down the thread followed by the circlip & then your metal plate.
Now place a flat washer & 17mm nut on the thread and as you tighten up gently the plate will press home against the flange which will enter the diff casing nice & smooth.
You now have both hands free & can get the plain circlip in the shaft recess with a couple of large screwdrivers.
Release your homemade tool & replace the shaft endcap. Voila !

Diff seal kit £9.40 incl vat from G & S part no. 31180

Offline richandhazel

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Re: HOW TO: Replace Drive Seals on Gearbox
« Reply #8 on: 28 September 2005, 02:59 »
Nice to see some input here from peeps that have obviously BTDT. I would just like to emphasize the need to undo that hub nut (for want of a better word) whilst you still have the car on the ground and with any luck, a willing volunteer willing to stamp on the brakes..........Its around 150 to 200 lb/ft torque required. Visa versa applies when reassembling :wink:

I made my own tool for the flanges, plenty of spare bolts and scrap bits and pieces :wink:

Judderi

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Re: HOW TO: Replace Drive Seals on Gearbox
« Reply #9 on: 07 December 2005, 09:10 »
I darent show you the way i did it. All i will say is Snap... Slice... Stab.... Bleed.... Argh..... Death... RIP....  :undecided: