Does anyone know the procedure to change the motor mounts on this vehicle? I am a limited DIYer and would be grateful for directions, hints, advice. Thanks.

It's your basic six cylinder motor mount job. Try a search - there should be quite a bit of information. For a self described limited DIYer it could be quite a handful.

Haven't done an M104, but I've done (or tried to do) a M103 twice. Generally seems to be that, of the four bolts securing the two mounts, three are pretty easy, and one is very, very hard.

On the bottom are either 17mm bolts or 8mm (?) allens. The allens are easy to round, so be careful with them. May want to shim up your allen socket with a little scrap of paper towel to take all the slop out. Also, if you're not careful, it's easy to lose a bolt in the crossmember. It once took me a couple hours to fish one out of that situation.

May want to have a couple of extra bolts on hand in case you round or lose one.

Also, soak the bolts in penetrating oil a day or two before you attempt disassembly.

On top are 17mm bolts. For the passenger side one, I put a box end wrench on the bolt, and levered a bar against it and a SOLID, structural part of the engine bay. For the driver's side, I did a combination of the above, plus lots of penetrating oil, and tapping on a wrench with a hammer. This one is the hard one, mostly because there's no clearance to get any kind of leverage on it.

If you're careful, you can lift the engine from the oil pan, by using some 2x4 blocks of wood spread along one edge of the pan and a floor jack. Jack up only one side at a time, and be careful of the clearance with the fan shroud and other engine bay items.

Loosen all the bolts, lift and replace one side, start bolts (but not tight), lift and replace the other side, torque bolts, and that's pretty much it.

Use a little anti-seize when replacing bolts. I forget the exact torque spec, it may be around 30 Nm.

OhioMike,

Did you end up doin the replacement? I have a 90 300CE and about to try to do mine.

Just curious how you made out. Thanks in advance for your input.

__________________
Dean

Just sold em all !! Curently driving a, 06.5 VW GTI

90' 300CE
Euro Lights w/wipers, Clear corners, 17" Monoblocks, K&N Airfilter, Sportline Suspension, Custom SS single muffler exhaust
80' 300D
96' Harley Davidson, XLH 1200

I Am Smart Enough To Know When I Should Not Mess With Something. Taking The Advice Of Other Members Of The Forum, I Will Hire This Job Done Since I Have The Parts.

I just did this last month.

Here is the post:

Oh boy! new engine mounts w124 1991 300CE




glenmore
1991 300CE
2000 C280
1990 LS400