How do I know if top mounts gone?

Need technical Q/A then you're in the right place

Moderator: martauto

Post Reply
User avatar
northloop
E30 Zone Regular
E30 Zone Regular
Posts: 944
Joined: Wed Aug 16, 2006 11:00 pm

Sat Sep 23, 2006 3:25 pm

There is a knock from the back of my old girl when going over bumps. That would generally lead me to think that I had a dodgey rear strut but it looks pretty clean with no signs of bleed or other wear.

Getting into the boot I can get the opposing strut to move when I wiggle the top by hand, the other side is rock solid with no movement.

Any thoughts, what's in there which can have gone? A bush, top mount or what?

Cheers in anticipation of your rapid replys :D

Gary
User avatar
thebigone
E30 Zone Regular
E30 Zone Regular
Posts: 294
Joined: Sat Jul 29, 2006 11:00 pm
Location: Newhaven (south coast)

Sat Sep 23, 2006 3:28 pm

Read the latest techno thread it covers tha very subject with pics :D
User avatar
northloop
E30 Zone Regular
E30 Zone Regular
Posts: 944
Joined: Wed Aug 16, 2006 11:00 pm

Sat Sep 23, 2006 3:51 pm

Just had a read and a look at mine ......... I cant hear any noises when i push down on the rear of the car, well nothing as described anyway. The top mounts also look to be in reasonable condition, not like those in the picture on the article. As a cheap part to change they might be worth doing anyway I guess.

Any other comments anyone?

Gary
User avatar
thebigone
E30 Zone Regular
E30 Zone Regular
Posts: 294
Joined: Sat Jul 29, 2006 11:00 pm
Location: Newhaven (south coast)

Sat Sep 23, 2006 4:23 pm

are your nuts tight :eek:
User avatar
northloop
E30 Zone Regular
E30 Zone Regular
Posts: 944
Joined: Wed Aug 16, 2006 11:00 pm

Sat Sep 23, 2006 4:26 pm

They sure are, it made the noises before I fitted the rear strut brace and obviously I checked how tight they were when I did that too.
User avatar
thebigone
E30 Zone Regular
E30 Zone Regular
Posts: 294
Joined: Sat Jul 29, 2006 11:00 pm
Location: Newhaven (south coast)

Sat Sep 23, 2006 4:43 pm

? how about no bumb stop???
User avatar
northloop
E30 Zone Regular
E30 Zone Regular
Posts: 944
Joined: Wed Aug 16, 2006 11:00 pm

Sat Sep 23, 2006 4:52 pm

The bump stops are in the boot but not fitted ..... :mad: what do they do?
Avner
E30 Zone Newbie
E30 Zone Newbie
Posts: 37
Joined: Sun Apr 30, 2006 11:00 pm

Sat Sep 23, 2006 6:43 pm

If you want to make sure it is the top mounts without buying new ones you can remove the shock from the car and go for a short drive on a bumpy road. If there is no knocking, it was caused by the top mounts (or the shocks themselves).
If the top mounts need replacing I think the the ones from a cabariolet are stronger.
Knocking from the back can also be the trialing arm bushes or the rear subframe bushes.
User avatar
northloop
E30 Zone Regular
E30 Zone Regular
Posts: 944
Joined: Wed Aug 16, 2006 11:00 pm

Sun Sep 24, 2006 9:28 am

thanks guys but what about the movement I can feel in the top of the strut if i wobble it in the boot. What does that point towards?
User avatar
Brianmoooore
E30 Zone Team Member
E30 Zone Team Member
Posts: 49353
Joined: Mon Jan 10, 2005 11:00 pm

Sun Sep 24, 2006 9:35 am

If you mean you can move the protruding top of the damper threaded end inside the boot, then your top mount has failed.
Unscew the 19mm bolt on the bottom of the damper and the two 13mm nuts in the boot and the damper complete with mount will drop out of the car. No need to even jack the car up on the RH side, although the exhaust may be just in the way on the left.
Replace them with E46 cab ones, 33 52 6 754 096, about Ԛ£12 each.
User avatar
northloop
E30 Zone Regular
E30 Zone Regular
Posts: 944
Joined: Wed Aug 16, 2006 11:00 pm

Sun Sep 24, 2006 5:38 pm

Thanks Brian, thats the answer I was looking for :D
320Touring
E30 Zone Team Member
E30 Zone Team Member
Posts: 12316
Joined: Fri Feb 11, 2005 11:00 pm
Location: Glasgow (Scotland)

Mon Sep 25, 2006 5:34 pm

http://www.e30zone.net/modules.php?name ... hmount.htm

should point you in the right direction dude-its a fairly simple job :cool:
The big Unit Parts Clear out Make me an offer on parts!
http://www.e30zone.net/modules.php?name ... 81#2766881
Post Reply