wicked vibration after motor mount - Page 2 - PeachParts Mercedes-Benz Forum

lowriderdog37 · #16 12-21-2008, 02:03 PM

AutohauzAZ. I opened them just as the thread about Chinese crap started.

theo3000 · #17 12-21-2008, 02:08 PM

Quote:

Originally Posted by lowriderdog37

AutohauzAZ. I opened them just as the thread about Chinese crap started.

I have the same mounts.

That's how I learned the diference between OE and OEM. They're made by FEBI, so they're OEM, but not OE. More a statement about FEBI than AAZ in my opinion.

I don't think they're so bad as to cause abnormal contact, but their durability is probably suspect.

MBeige · #18 12-21-2008, 02:25 PM

I'll chime in, since I just recently installed factory (MB dealer) mounts and have the same vertical vibration at speed. However, at idle, it's only a little shaking due to worn dampers.

They're supposed to lower a little due to the weight of the engine, but they should do so equally I believe. While I haven't had the chance to check if both went down evenly on mine I do recall that the old ones were much lower than the new ones even when lowered.

lowriderdog37 · #19 12-21-2008, 03:02 PM

I am not getting vertical touching any more since I lowered the trans.

I figured the mounts would settle after a few weeks, at least a little.

I get no vibration at idle, none at all. Now I only feel shaking when I am above about about 1k rpm.

I have used Autohauz for many items...they usually have a good price and they are pretty good about getting stuff to me. Just these mounts are in question to me.

Hatterasguy · #20 12-21-2008, 03:07 PM

Maybe your flex discs are used to flexing in a certain way, and now you have changed the angle a bit with your new mounts.

Describe the vibration further, if you pop it in neutral does it go away? How about when you are on the throttle? Is it RPM related or speed related? If your going along in 4th and its vibrating, does shifting down to 3rd change anything?

barry123400 · #21 12-21-2008, 05:16 PM

I know certain companies take motor mounts as cores. I imagine they clean up the metal components and pour new rubber in with the parts in a jig. Not very likely on these older mercedes. More a thing with antique vehicles.

You just may have a set of mounts with very firm rubber is a possibility. If so they will probably soften a little with use. Also it should not be forgotten that certain problems with an engine may be contributing to it as well.

With the old sloppy mounts it is possible they covered it up a little by excess damping. Just a thought.

I might loosen off each injector line at each injector one at a time watching for any change other than what would be normally expected. In otherwords make sure the engines power balance seems about equal. No one given cylinder making a larger or lesser contribution compared to the others.

jfowler · #22 12-21-2008, 07:26 PM

Did you disconnect fuel for any reason? You may want to make sure this isn't about air in your fuel system causing rough running/idle.

locry · #23 12-22-2008, 05:19 AM

one mount will always be more "crushed" because of engine torque

leathermang · #24 12-22-2008, 08:55 AM

Have you found the FSM information yet ?
I think it is available online...
If you do not adjust them properly when installed all this other is speculation.

lowriderdog37 · #25 12-22-2008, 01:38 PM

The vib is strictly engine/RPM...it will do it in neutral, or any other gear. It is a very fast vibration if that helps at all.

I was thinking in the beginning that it could be harder rubber, and needed some breaking in...that's why I am giving it a little time now. One thing that does strike me as odd is that you can't see my motor shaking at all (with the old or new mounts). You can see the accessories shaking like he11 all around it, but the engine looks solid.

Fuel has not been disconnected at all since the replacement, and I have been getting full power. I am pretty sure there is no air in the line...I cannot see any in the prefilter, or in the clear line coming from the IP.

I haven't found the FSM stuff yet, I don't even know where to look since the old copies (from that 1 site) went away. Sorry, I can't even remember his name now. If I take the bolts out now, everything lines up perfectly...given I don't know how it is "supposed" to sit, but it's all lined up to sight. I even did what was suggested earlier to loosen everything and let the engine run....it didn't move a bit.

Like I said before, it was a LOT worse with the forward-aft facing bolt in the trans mount. I think I am going to take the metal tube out next to see if that helps at all. It was connected but sat loose in there with the old mounts, and is very tight in there now. That might still have something to do with it. I am going to play with that tomorrow when it's warmer.

lowriderdog37 · #26 12-23-2008, 04:39 PM

GOT IT! I took out the metal tube facing foreward/aft on the trans mount. It was sitting in the cradle pretty tight, and after I took it out, smooth as butter. If I didn't know any better, I would have thought I was driving a Mercedes.

I am not to worried about the movement of the mount...the old mount had a tube, but the hole in the mount was worn right off of it, so it had so much wiggle room it wasn't doing anything anyway.

Thanks all for the suggestions.

MBeige · #27 12-23-2008, 05:59 PM

Interesting, now I have more reason to do the transmission mount.

On my case however, it comes and goes. Sometimes if the highway is smooth at 80+mph there's no vibration. When there are undulations, I can feel it a bit amplified.

lowriderdog37 · #28 12-23-2008, 07:18 PM

I do now have a vibration that is audible only (no feeling) in 4th at about 45mph. It is really loud, but I am ready for my drive tomorrow, so I am happy for now.

I have had this vibe I speak of here since the new mounts as well...so we'll see. I have been doing a lot of work on suspension and drivetrain lately, so it could just be something loose making noise. I just need to stick my head under the car at 45 mph to see where it's coming from.