Check Out This Broken Motor Mount!

[Isaracing]

This was from auto-x - sheared right in half. I got some Ireland Engineering poly's is there now. This was from a couple weeks back, but I just got the pic up. I thought it was pretty cool.

<img src="http://www.millerisar.com/mount.jpg">

[shim]

damn

[e30-323ti]

Tell me about it!!

I did both sides at once with the new enigine!!

I also have IE poly mounts now, they seem to be holding up, but they noticeably transmit more vibration/noise, but I don't care!!

[Erik@EDGE]

Dang@!

[jmott]

I did better than that.

Tore the metal out of the crossmemeber. Had to get a new crossmember.

Your way looks cheaper though

[randywalters]

This was from auto-x - sheared right in half.

Very common on the E30 6-cylinder cars at the autocrosses. Primary cause is a missing rubber drivetrain buffer that causes the engine to shift forward under hard braking and that shears the mounts (BTDT). Usually when an E30 shears it's mount i find this buffer is missing. I inspect my buffer at every autocross and keep spares in my trunk! Is your drivetrain buffer there or is it missing?

Secondary cause is non-smooth driving and jumping on the throttle too hard, all made even worse if the mounts are old or have a lot of miles on them (like 80K kinda miles).

My mounts are stock and are 4+ years old with over 30K on em and they're surviving well

[nukblazi]

Buffer? Sorry, I am new to my e30.

[vodomagoo]

it happened before my swap blew both and the engine fell toward the rad screwing up both hoses, i then switched to turner hd mounts there e9 or e12 mounts with alum caps preventing flex. the mounts just alone work awsome and with the caps there super still.

[randywalters]

Buffer? Sorry, I am new to my e30.

The Drivetrain Buffer is bolted to the underside of the oil pan/bell housing area. It consists of a small metal arm with a rubber buffer snapped into the end. Under hard braking this rubber buffer pad snubs up against the backside of the subframe and prevents the engine from sliding forward while braking hard. This is a very important piece if the car is autocrossed. I learned about it the hard way when i first got my E30 - i broke a few engine mounts before i figured out that this rubber piece was missing from the arm and how important it is to have it.

If this metal arm is not there, or if the arm is there but the rubber buffer is missing, the engine can move forward enough to shear the engine mounts even if they are still in decent shape (i've seen this on various E30 at autocrosses).

Also, if the car is an 84-87 6-cylinder model then the lower radiator hose gets cut by the power steering pump pulley when the engine shifts forward. For the 88-93 E30s BMW redesigned the hose routing and radiator to prevent this hose-cutting problem of the earlier cars. I've also seen (and heard of) cars where the engine slid so far forward that the fan chewed up the radiator after the engine mounts sheared (possible on all years).

You guys that drive your 6-cylinder E30 hard should look under your car and see if it has a drivetrain buffer, and if so see if the rubber pad is still there - this thing takes a lot of abuse and i lose a few per year so i always keep a spare buffer in the glovebox. If you find that you don't have the metal arm at all check to see if you have the two bolt holes in your bellhousing piece where this arm bolts in. If you have to buy the arm, also buy the two bolts because they're probably longer than the ones already there, if any.

Here's an ETK pic (items # 14 & #15 at the bottom):

[BMuu]

I tore the corssmember and the motor mount on my 94' 325is from drag racing and just overall driving hard.