[Vwdiesel] changing drive axle flange seals

[Sandy Cameron]

Note to others,:
Since the listbot (fortunately) does not handle attachments, if you want the
picture, email me and I will send it direct.
Sandy


At 05:22 PM 3/15/04 -0500, Paul Engle wrote:
>My tranny started leaking gear oil around the driver's side drive axle
flange. The >seals are fairly inexpensive. Will I nned any special tools to
do this job? How >exactly do they come off. Just started looking in Mr.
Bentley and shows some >special tool. Can it be done without it? Please advise.

It can be done, easiest with tranny on bench, but for younger gymnasts, can
be done on hoist or jack stands.

The flanges are pre-loaded against the circlips to pre-load the internal
roller bearings the flange stub runs on..

While removing the circlips without the tension released is possible, it is
also very exciting. Not recommended. Safety goggles and hard hat recommended.

I consider anywere Bentley says "Volkswagen special tool # # # # required"
to be an outright challenge, so the attached picture shows how I did it.

Remove the 6 inner axel flange bolts for each axel using the proper 12 point
bit, (metric) a set of 4 avaiable at any FLAPS (very reasonable).
.[The largest fits the head bolts, the next fits the starter bolts, the 3rd
fits the flange bolts, and I have not found a use for the smallest yet]
(clean out the hole with a screw driver and drive the bit all the way home
with a hammer before undoing to avoid stripping the internal spline.)

I find the easiest way to take out the flange bolts is to put the front end
on jack stands (  it helps to jack the body or subframe so the hubs can hang
down) and remove the wheels, then you can get at them from under the fenders
through the wheel wells. I bought a realy cheap 3 foot long 3/8 socket
extension, (under $10 for a set of 3.) You may need someone to stand on the
brakes while you break them loose.

After the bolts are out,  to let the axel C/V joints fall free from the
tranny (they are in the cup-like recess in the flange),  turn the steering
hard over in the direction of the one you are taking out (full right for
right axel, left for left)  This achieves maximum extension of the axels and
helps set them free..

Bag the C/Vs to keep dirt out.

Once the insides of the flanges are cleaned out, you can pop out the rubber
plug with a small screwdriver or dental pic, and you will see the circlip,
and under it, a dished washer. TAKE NOTE when you remove the washer, which
way the "dish" faces, and write it down.

Now you have to compress the unseen spring inside the diffy unit

Using my method, you find a stiff steel bar with a hole in (or make one),
and a metric bolt that fits the threaded hole in the flange stub. If you
can't find a bolt, borrow one ot the upper bolts that holds the tranny to
the engine block. That's what I used.

There is a problem here, as the threaded hole in the stub is not deep enough
to achieve the full travel required to relieve the spring tension. (sigh, VW
does it again) If you can get a bolt this size that will take a nut at each
end, or threaded all the way to the head, so you can use a nut to run it the
rquired distance to release, you could do it that way. That's why the
Bentley tool has a nut on the outer end. You could take your tranny bolt to
the local boltmiester and get a threaded rod about 6" long and a couple of
nuts, or.... you could do what I did.

I took 2 of the original flange bolts and cleaned the grease off of them (we
sure don't want them to slip) and threaded them part way in to opposite
holes in the flange. I then screwed the center bolt in about 3 turns to
engage a bit of thread. I then UNSCREWED  the 2 flange bolts against the bar
with small vice grips, untill they seemed tight enough, and took some of the
distance the center bolt must go before it bottoms in the hole.

I did this with the tranny on the bench, and it seemed just too easy. I
don't know what a torture trick it would be lying on your back under the car.

You could roll the car up on its side on an old mattress like I did once to
fix the gas tank on a rabbit)

As you compress the flange, be watchfull about 2 things.

1. IMPORTANT make sure the "pusher" flange bolts remain centered on the bar.
(next time I do this I will drill 2 "pockets" in the bar for the bolt heads
to fit into, to prevent slippage).

SAFETY GOGGLES ARE HIGHLY RECOMMENDED
All usual disclaimers apply here.

2. While slowly compressing the flange against the unseen spring, keep
testing the circlip and washer with a dental pick to determine when the
pressure has been released. Then fiddle the clip out with whatever you have
(I managed with 2 screwdrivers , remove the dished washer NOTING which way
it faces (and writing it down if you are over 40).

You now release the pressure by unscrewing the center bolt (or its nut, if
you got one like that). Note that if you did it my way, there will still be
some spring pressure when the bolt comes out of the stub, so don't get in
the way as it pops off..

The flange should now just slide off the stub spline. If it does not, apply
a puller being carefull not to dammage the threaded hole in the stub.

I would recommend you not remove the spring and other parts behind the
flange, as it is possible to forget how they go back together. (someone on
the group got into that jackpot) When you pull the flange out, make sure
there are no washers or other parts come away with it. Sometimes the grease
glues parts to the back of it, and you don't notice until they fall off on
the floor.... out of order.

As they say in most manuals (cheerful bastards) "Assembly is just the
reverse of removal"

I've done it [on the bench] and it's not rocket science. New plugs come with
the seal kit, be sure to use them, or tranny oil will get into the C/V joint
and trash it.

Since the flange is actually part of the C/V enclosure, it would be wise to
fill in some more C/V grease to replace what you lost when you cleaned the
flanges.

BE SURE TO REPLACE THE RUBBER PLUGS BEFORE GREASING !

Changing the seals is pry-bar and hammer work. You can drive the seal in
using a small chunk of 2x4 against it, and hammer gently in the center of
it, or you can push it in using the bolt from your compressor, and a plate
bigger than the seal with a hole in the center for the bolt.

The most tedious part of the job is fiddling the circlip out and back in
without spreading it too much...

Sandy