850 Motor Mounts

1995 850 GLT 100K
Having replaced the right passenger side and top motor mounts I have been checking out the others, trying to fix a persistent vibration being transmitted from the engine bay at idle, particularly when in gear at a light or in park. I notice that the rear center motor mount has two clips embedded in it, on my rig one of those clips has popped out of its seat and is dangling by the rubber band that links the two together.
1.) What are the clips for? Does the clip dislocation signify that the mount is worn and needs to be replaced? Should I just cut the clip loose and run with it as is? Would this be a source of the vibration?
2.) The top motor mount is the poly unit from IPD and it is bored off center, in other words, so that it works like an eccentric cam. Anyone else have experience with this? I don’t know if it is supposed to be adjustable or is defective, and if adjustable, just where should you adjust it? I positioned it so that the mount pin would be as far from the firewall as possible. I still get a sharp bang from the engine bay when I start it up, it sounds like something is shifting violently into position. It’s been doing this for a long time, I just got tired of letting it go, something needs to be fixed.
3.) Anyone have experience with changing the big lower front and rear motor mounts in an 850? Any tips? It looks like a real bastard job since the entire engine sits directly on top of both mounts. I have the typical garage access, ramps and jacks so there isn’t a lot of room for this garage mechanic to manuver. It looks like you just about have to pull the engine to access these things.
I’m pretty fearless when it comes to working on my daughters 1991 240, but I’m a bit more reluctant when its my primary transportation that’s laid up for a week while I try to fumble a solution with make shift tools. I have replaced the PNP switch, thermostats and tuneup stuff, but I haven’t tried to tear out anything with a gasket on it yet. I’d turn it over to a shop but it looks like one of those $1000 jobs and right now it’s just annoying. I’m afraid that if I let it go it will be causing more wear on the rest of the drive train. Thanks for any answers on any or all of my problems.

The offset hole in the IPD bushing is intentional. As I recall, there are a couple of arrows (>>) on each piece adjacent to the hole and should be oriented so that the hole is nearest the firewall. If I read you right, yours if rotated 180 out. Also check the condition of bushing at the firewall.

I haven't replaced my engine mounts (yet?) but think a floor jack under the engine (put a board or suitable peice of thick plywood between the jack and engine) might work. I think they're all replaceable with the engine in place.
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Erwin in Memphis, '95 855t - fast & comfy, '86 Guzzi LeMans - fast & loud, '76 Montesa 348 Cota - slow.

FYI,

I was reading my Haynes last night and it indicates that all engine mounts can be replaced with engine in place. FWIW, They also state that you may need to remove items that interfere with removal of the mounts. Sounds ominous.

Also, the woodblock on a floorjack is acceptable but, again, according to them, don't lift the engine more than 1.2 inches if needed, or the left inner CV joint will be damaged.

Again, I haven't done this but am just passing on the information I found last night.

Good luck,
--
Erwin in Memphis, '95 855t - fast & comfy, '86 Guzzi LeMans - fast & loud, '76 Montesa 348 Cota - slow.

Thanks for the info. I'm not sure whether the answer is to jack up the engine or suspend it while you drop the car, same thing either way 'cause they do warn not to move it more than 30mm to avoid the CV damage. I asked at the dealer and apparently the clips on that mount are to "keep the mount from separating and falling out if they break". This is the parts guy. Still a curious setup. No way you can get the mounts out by raising the engine an inch and a half. I'm going to replace the horizontal one because I can get to it and leave the others until they actually fail or I have to do some major engine work or have to separate the CVs from the transmission for R/R. I'm going to post this again because the parts guy said that the mechanics know when the motor mounts have failed due to the distance from the engine to the subframe, ie, when it sinks enough you will know.