Hi all!
I spoke with my finnish friend Juubi about translating his DIY to english... so here you go.. correct my language please :)
Original page here: http://juubi.hlan.net/index.php?page...x/transfercase
So the car is BMW e30 325 -89
Parts used in service:
Seals 2x ( front shaft)
Seal for rear shaft
Seal for input shaft
paper gasket for case
ATF oil 0.5 litre
Transmission oil 1.25 litre
So i noticed need for service when i was driving snowy road with summer tires on. All went fine till
rear end started to slip and torgue was lost from the front end fully to rear. I was able to proceed
moving with lot of throttle but thinking about traction there was no any reason to continue this way.
So viscous coupling located in transfer case has come to the end of its life.
Factory Brand new viscous would cost something around 2000 euros, so that wasn't even a option for me.
Viscous is assembled in the vacuum space, welded by robot, so i thought that it would not be reliable
option to repair it myself. Only changing the viscous coupling makes that much work that changing it
just for a test would be unnecessary. Luckily i found
full TC for suitable price, which had fail on its front axle splines. Transfer case that i bought included
100k km drived viscous, but at this part i could not test it but only rotating by my own hands..
The repair itself started by removin exhaust, exhaust covers, front shaft, transfer case support and rear shaft.

Dropping of the engine was quite fast attempt. Needed to remove front subframe bolts, steering rack,
power steering and radiator hoses. After that i was able to drop engine for transfer case remove.
Dropping of the engine pictured in front of the car.

I needed jack with support tranny so i supported engine with the chain.
After removing all the parts and lowering the engine, i was able to remove the case itself.

Transfer case is bolted to the tranny with 4 bolts, also jointment between tranny and T case has 3 bolts per flange.
Removing these bolt will drop the transfer case.
Transfer case ready for service and change of viscous coupling.

Case had some oil leak from breather and front seal. Glory itself was washed with pressure washer and all hardened oil
was removed from the case before starting to tear it apart.
I choosed best parts from these two transfer case and build it togehter.

After that i was able to start disassemply.

Shell will split after removing all M8 bolts off around shell. It needs little rubber hammer because 2 liners.
on the background you will see car front end and drive shaft of the other side..
Disassemply of T-case

After splitting shell you lift gear off with the puller, rest of the parts will loosen with rubber hammer

Checking chain

My old chain felt little loose. You can measure chain looses by twisting chain on cross-direction,
over 200k km is able to see on this chain.

comparing old chain to newer..
Viscous next to each other

Here is my spare and old viscous. It is impossible to measure the condition of viscous by eyesight but
in this case you couldonly guess which one is cleaner
Now its right time to replace seals to T -case.

There is no any counterface for seals where to tap new ones. You should measure the depth before removing old one.
At this part i used washers to measure correct depth.

To be continue...

After installing all seals, I was able to start put it back together

It all started by installing input shaft to case. Its locked with lock ring.
Then its time for gear and viscous crown.

Then you drop the planet gear onto it.

for a point on a "i" you'll drop the unbroken viscous onto it.

Preparing the rear cover

Chancing rear cover seal is done by same technic like i showed earlier. Using washers.

Here is Ix's saddly failed front output gear. Luckily i got another one with splines that are in good shape.

Installation of chain, i took old bearing from spare T case, which was in better condition.

All things together, ready to install rear cover

Making of gasket

Cover installed

While Transfer case is off, you should check your tranny output shaft seal too and all rubber mounts etc.

then you can start to put it all back together..
I spoke with my finnish friend Juubi about translating his DIY to english... so here you go.. correct my language please :)
Original page here: http://juubi.hlan.net/index.php?page...x/transfercase
So the car is BMW e30 325 -89
Parts used in service:
Seals 2x ( front shaft)
Seal for rear shaft
Seal for input shaft
paper gasket for case
ATF oil 0.5 litre
Transmission oil 1.25 litre
So i noticed need for service when i was driving snowy road with summer tires on. All went fine till
rear end started to slip and torgue was lost from the front end fully to rear. I was able to proceed
moving with lot of throttle but thinking about traction there was no any reason to continue this way.
So viscous coupling located in transfer case has come to the end of its life.
Factory Brand new viscous would cost something around 2000 euros, so that wasn't even a option for me.
Viscous is assembled in the vacuum space, welded by robot, so i thought that it would not be reliable
option to repair it myself. Only changing the viscous coupling makes that much work that changing it
just for a test would be unnecessary. Luckily i found
full TC for suitable price, which had fail on its front axle splines. Transfer case that i bought included
100k km drived viscous, but at this part i could not test it but only rotating by my own hands..
The repair itself started by removin exhaust, exhaust covers, front shaft, transfer case support and rear shaft.

Dropping of the engine was quite fast attempt. Needed to remove front subframe bolts, steering rack,
power steering and radiator hoses. After that i was able to drop engine for transfer case remove.
Dropping of the engine pictured in front of the car.

I needed jack with support tranny so i supported engine with the chain.
After removing all the parts and lowering the engine, i was able to remove the case itself.

Transfer case is bolted to the tranny with 4 bolts, also jointment between tranny and T case has 3 bolts per flange.
Removing these bolt will drop the transfer case.
Transfer case ready for service and change of viscous coupling.

Case had some oil leak from breather and front seal. Glory itself was washed with pressure washer and all hardened oil
was removed from the case before starting to tear it apart.
I choosed best parts from these two transfer case and build it togehter.

After that i was able to start disassemply.

Shell will split after removing all M8 bolts off around shell. It needs little rubber hammer because 2 liners.
on the background you will see car front end and drive shaft of the other side..
Disassemply of T-case

After splitting shell you lift gear off with the puller, rest of the parts will loosen with rubber hammer

Checking chain

My old chain felt little loose. You can measure chain looses by twisting chain on cross-direction,
over 200k km is able to see on this chain.

comparing old chain to newer..
Viscous next to each other

Here is my spare and old viscous. It is impossible to measure the condition of viscous by eyesight but
in this case you couldonly guess which one is cleaner
Now its right time to replace seals to T -case.

There is no any counterface for seals where to tap new ones. You should measure the depth before removing old one.
At this part i used washers to measure correct depth.

To be continue...

After installing all seals, I was able to start put it back together

It all started by installing input shaft to case. Its locked with lock ring.
Then its time for gear and viscous crown.

Then you drop the planet gear onto it.

for a point on a "i" you'll drop the unbroken viscous onto it.

Preparing the rear cover

Chancing rear cover seal is done by same technic like i showed earlier. Using washers.

Here is Ix's saddly failed front output gear. Luckily i got another one with splines that are in good shape.

Installation of chain, i took old bearing from spare T case, which was in better condition.

All things together, ready to install rear cover

Making of gasket

Cover installed

While Transfer case is off, you should check your tranny output shaft seal too and all rubber mounts etc.

then you can start to put it all back together..

Comment