|
|
Cost: $50
Difficulty:
Time: 4 hours
Torn bushings: up to a day
|
Procedure
and photos courtesy of Jeff Nord
|
Failure syndromes:
Rear clunk noise when you disengage the clutch on an upshift
/ down shift; especially an upshift. when accelerating; the subframe
is pulled away from the chasis via the wheel torque. when you push
the clutch in, the subframe unloads and hits the chassis creating
the thunk.
The rear of the car feeling like it steers itself. Probably
best to do the rear pitman arms first before the subframe bushings
if you have a self steering rear. or, at least have them inspected.
If the pitman arms are good then this means the bushings are soft.
No real way to inspect the bushings visually. however, if you support
the subframe, you can easily remove the arm covering the bushing
and see how torn it is.
You will need some specific tools to do this repair. Parts cost
= 2 x $40 for bushings. labor with puller and lift, no torn bushings
is about 4 hours. Labor with a torn bushing (you can't use the puller
then) can be upwards of a day - you have to cut the bushing out.
to cut it out, you may have to remove the subframe.
|
Subframe mounts vs subframe
bushings:
I just got the bad news that the part that I
recieved from BMA was wrong!
I ordered the "bushings" instead of the "mounts".
The "bushings" are a horizontal item located on
the subframe and the "mounts" are mounted vertically
into the chassis.
So to make this easier for other people ( as well as cheaper,
now I have to pay double bacause I can't wait for BMA)I'm
giving you the part #'s for the job.
Patick @ BMA has told me that the "bushings" and
the "mounts" are the same for "all" E34's.
Subframe "Mounts" # - 33-3-1-129-760 $25.00 ea.
For vertically mounting from subframe to chassis.
The picture on Bruno's site would be # 2
Subframe "Bushings" # - 33-17-1-131-903 $20.00
ea.
The picture on Bruno's site would be # 3
Even Patrick told me this can be a very confusing item for
people to order, because BMW lists them both as "bushings",
but as you get more into the ordering screen, it finally shows
the correct one as being a "mount".
Take it from me, it just happened today.
Keith '95 540
|
Procedure |
- Floor lift preferable, jackstands, BMW Bushing Puller Tool
|
1. First, a nice shop with a lift helps. This
is the shop of Dan Patzer, one of the Puget Sound chapter tech advisors.
Dan will work with you side by side on car repairs. I enlisted Dan's
help because of his extensive shop and bushing puller.
|
2. Car in the air, here's our target
from below. The subframe bushing is located under the large nut on
the right hand side of the picture. The bushing locates a 'pin' that
goes thru the chasis and keeps the subframe in place. To do this repair,
you need to work in both the car's cabin and from underneath. First,
support the subrame with a 4x4 on a jack. Then, remove the arm in
this picture (note: two 13mm mounting bolts are obscured in this picture).
|
|
4. This is in the cabin with the
backseat removed. Underneath this tar patch is the bushing pin. Peel
away this patch to access the pin. This patch is located near the
seat belt buckle on the floor pan. You'll also need to remove the
outboard rear clips for the seatbelts. |
|
|
5. With the patch removed,
you can see the top of the pin that locates the subframe. We are going
to remove this pin. |
6. Underneath again, subframe arm removed, you
can see the actual subframe bushing. At this point, the subframe
itself is being supported by a 4x4 post on a jack. The bolt in the
center is the pin previously mentioned. You need to hammer the pin
up and push it out of the bushing. Be ready to hit it hard. Don't
mess up the threads! Put the nut on and hammer on a socket!
Pin shown removed on the right.
|
7. By lowering the jack
that was supporting the subframe, the subframe drops away from the
chassis. You can see the space in the picture. |
|
8. Using a special BMW tool, we'll now pull
the bushing out of the housing. It's a tight, press fit. On the
left is the tool partially setup. NOTE the puller's
top plate in the space created by lowering the subrame? On the right
is the tool installed and starting to pull the bushing out.
|
9. The bushing stretches as the puller digs
in. We used a heat gun on the sides of the subframe to help loosen
the bushing. On the right is the bushing
coming out. Watch your toes - it will drop to the floor.
|
|
10. New and old bushing
side by side |
|
11. To install the new
bushing, you reconfigure the BMW tool to press the new bushing
in. Trim the excess rubber away.
We strongly recommend that you DO NOT
lube the new bushing with undiluted detergent to aid the installation.
Instead, we suggest only water or an extremely diluted detergent
solution. Using too much detergent (lube) appears to cause the
subframe to slip up the bushing when driving. The bushing /
subframe connection appears to rely on friction and the detergent
does not disipate enough leading to slippage. |
12. Once the new bushing is installed,
you have to replace the pin. Here's a shot of the pin and
the hole in the cabin. Note the knurling in the pin. The pin
is forced into the hole and the knurling holds it tight.
Putting the pin back in, you will need to line up the new
bushing below so you don't gouge the threads on the pin. Do
this by carefully jacking up the subframe so the pin and the
bushing line up. Firmly hammer the pin back into the chassis.
Be careful not to mess up the threads! :)
|
13. Here's the new bushing and the pin
replaced. At this point, replace the subframe arm, torque
the bolts and then lower the jack supporting the subframe.
Go do the other side.
|
|
Big thanks to Jeff Nord and Micah O'C
|
|
|
|
|
©2000 BMWE34.net
|
-
Home of the Bmw 518i, 520i, 524td, 525tds, 525i, 535i, 530i, 540i,
M5 and other Bmw E34 chassis -
|
|