Author Topic: Rockauto M42 Motor Mounts  (Read 4485 times)

keflaman

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Rockauto M42 Motor Mounts
« on: June 28, 2012, 11:02:08 PM »
Pondering the purchase of installing an alternate to stock motor mounts, I read where some member(s) bought and installed M42 motor mounts from Rockauto and were happy with them, so I thought I'd give it a go. http://www.rockauto.com/catalog/moreinfo.php?pk=3460080

What I failed to notice in the link above was the difference in mounting points between the stock and Rockauto mounts and I immediately realized that there may be a problem. Secondary to that I realized I had burned the original boxes with receipts therefore rendering a return impossible.:o


After studying the situation for a few minutes I took some measurements and applied my somewhat rusty background playing Tetris to come to a solution: File a few milimeters off the inside edge of the alignment tab...


...and install thusly...


I also added a large, thick steel washer underneath to distribute the stress more evenly on the subframe and prevent cracking...


Same process to the right side of the motor. Yes, I forgot the heatshield, but this is a temporary replacement motor I installed while I freshen up the original motor.


That's all there was to it. Not exactly plug-n-play, but with a little filing everything went together smoothly.

And let's talk about smooth...I finished the installation of my motor and took off on a little test drive. At the first stop sign I slowed down, looked both ways and thought I felt the car die. A quick look at the tach verified the engine was still running!

I was impressed to say the least, so now it's a matter of time to see how durable these mounts are. Pricewise, they're more expensive than the E28 mounts I was going to go with, but they are drastically cheaper than OEM mounts and worth the money if they only last half the time as original.

DesktopDave

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Rockauto M42 Motor Mounts
« Reply #1 on: June 29, 2012, 07:19:16 AM »
I didn't even know they had these parts.  I'll have to check them out - mine are pretty bad.

I love RockAuto closeouts - just overhauled my e24 master cylinder for $33 shipped!
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

keflaman

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Rockauto M42 Motor Mounts
« Reply #2 on: June 29, 2012, 01:50:15 PM »
I'll second love for Rockauto closeouts. I bought a Beck/Arnley crank bearing set from them at closeout. When I opened the Beck/Arnley box I discovered the bearings were actually Glyco which was listed on the website right under the Beck/Arnley bearings for $30 more!

Here's a picture of the motor mounts I took out of my car. Imagine looking at them installed in the vehicle from the rear looking forward. The LH mount isn't so bad, but the RH is definitely deflated. The Rockauto mounts are ~5-6mm taller, but there is no rubbing on the hood or vibrations from the driveshaft noted.