Tips needed for Motor Mount replacement - PeachParts Mercedes-Benz Forum

#1 04-26-2002, 07:39 PM

Well I searched the forum and did not find any info on DIYS motor mount replacement. I will be doing the replacement this weekend and would appriciate any tips for making the job successful. I have a 1987 420SEL and will be replacing both mounts. All tips and tricks will be greatly appriciated.

Thanks!!!

euro 287 · #2 04-26-2002, 09:11 PM

Remove 8 allen in center of subframe underneath mount. Somehow lift motor safely, I use a screwjack on the lift. After getting motor up about 6 inches , try to clean out holes for 6 allens. I use a 6 quarter inch drive stubby from snap on , but you might find one at your locak parts store. After removing the two bolts mount will come out. Be sure to start all bolts by hand before tightening them. It helps alot if you can gain access to a rack. A place down here rents racks by the hour 35.00 . not bad but you have to sign a liabilty waiver . Sorry couldnt help any further.

#3 04-29-2002, 10:28 AM

Thanks for the tip. Well I got it done. Man those inside allens were brutal to get at!

euro 287 · #4 04-29-2002, 10:39 PM

I have seen people round them. Now that becomes a pain. Here is another tip for all of you DIYers. If you have a allen starting to round or you think it will round STOP and get some valve lapping compound, put it on the end of the allen socket and that stubborn allen will brake loose.

sixto · #5 04-30-2002, 04:02 PM

Quote:

Originally posted by euro 287
If you have a allen starting to round or you think it will round STOP and get some valve lapping compound, put it on the end of the allen socket and that stubborn allen will brake loose.

He tells us after I drill out that stubborn OM603 intake manifold bolt

Sixto
91 300SE
87 300SDL
81 300SD

mbtjc · #6 04-30-2002, 09:58 PM

Ok, this probably sounds really ignorant, but what the hell! Is the one 8 allen what holds the motor to the mount and the two 6 allens what holds the mount to the frame? And when jacking the motor up, where do you want to position the jack? Do the allens need to be torqued? Also, how difficult is it to replace tranny, diff and rear subframe mounts and the engine shocks? Sorry for the string of questions! Any help obviously appreciated.

euro 287 · #7 04-30-2002, 11:48 PM

I take a board on a jack, put it underneath the oil pan . You will have to take the shocks loose to do the mounts, so you can replace them if you want. Usually when doing motor mounts I replace the tranny mount also. I rarely ever do diff , rear subframe mounts. No torque on the mounting bolts just tight. Yes the 8 allen holds the motor mount to the mount arm and the two six allens hold it to the body. Good luck.

mbtjc · #8 04-30-2002, 11:58 PM

Awesome...just wondering, why do the shocks have to be loosened?

#9 04-30-2002, 11:59 PM

another thing, only do one side at a time. if you remove both 8mm bolts at the same time lining up the engine becomes hard.
also place some kind of support (block of wood etc.)under the strut so the engine turn your fingers to hamburger when you are playing with the 6mm bolts, and the jack with the board slips. oteh wis e you seemon the right track.

MikeTangas · #10 05-01-2002, 01:13 AM

You have to loosen the engine shocks because they will limit the amount of lift you get when jacking the engine up. You'll need all the clearance you can get. Might also watch the fan shroud closely, maybe even loosen it, just in case.

autozen · #11 05-03-2002, 12:34 AM

Mike,

Are you saying that Georgia folks are dumb or stupid?

Peter

mbtjc · #12 05-03-2002, 12:46 AM

I'm pretty sure Mike is referring to the accent. ID as in idea or "idee" as country or southern folks say it, trust me, my grandparents live on the Missouri/Arkansas border, this is how they speak. So it would go "Got any idea?....About what?"