CRAPP!! weird vibration, PLEASE PLEASE Help!!!!!!

[87-325ic]

its two much to be the urethane mounts.. its really bad.. if they cause it, then it was preexisting and they make it much much more noticable..

i did just put them in, so there are no cracks yet..

and the old stock mounts just went out in the trash.. i dont think they are to blame, unless the old ones just absorbed ALL the shock,
cuz its BAD now..

[DanielHStout]

I couldn't see it being an issue with the crank. That front bolt is torqued to an ungodly spec. Plus think about it... the crank gets so many extreme forces exposed to it that it would be crazy to think that somebody reaming on the damn thing could possible damage it. When you were fucking with the rear mounts and tranny seals I would think that the pivoting motion on the motor mounts could have damaged them. How low did you drop the rear of the tranny? Was it always supported. Mix manged motor mounts with urethane tranny mounts than your bound to have a pretty fucked up vibration going on. Without actually hearing it its hard to say though. Get a long extension and use it to listen to different parts while the motor is running.You should be able to localize it that way. And if it is really as bad as you say then you might be able to actually see some shit shaking around under the car or under the hood. Unless of course it does have something to do with the flywheel or the crank ect. but I find that to be very unlikely. Just my logic.

[87-325ic]

i did, nothing appears to be shaky..

the tranny was always supported, and never dropped enough to touch the crossmember.. only enough to get the the bitch clip and to swap the mounts..

i dont see where its this bad from mounts..

you can only hear it, and Feel it, in the cabin..

id be happy to get a sound clip for you..

[DanielHStout]

You had to have undone the exhaust to do the work right. Maybe you just didnt get the exhaust back together right and its vibrating on something. I dunno man thats all I got. A "quality" sound clip might help.

[87-325ic]

its not exhaust, its definately something in the engine, between the crank and transmission..

i tried to get a clip, but it was useless.. as theres more of a thump, than there is a sound..





Help!

[porsche gt1]

its not exhaust, its definately something in the engine, between the crank and transmission..

i tried to get a clip, but it was useless.. as theres more of a thump, than there is a sound..





Help!

I think you just answered your own question. There is only a very select number of parts between the crank and the tranny. I think you are going to have to take your tranny off and check all the parts. If it is a bad flywheel it will not lie flat on the ground. Maybe it is your clutch, pressure plate, TOB, Slave cylinder, who knows... you say you have checked everything under the car all you have left is the interior mechanical components. I say if it is bugging you that much get in there and figure it out.

[DanielHStout]

I think you just answered your own question. There is only a very select number of parts between the crank and the tranny. I think you are going to have to take your tranny off and check all the parts. If it is a bad flywheel it will not lie flat on the ground. Maybe it is your clutch, pressure plate, TOB, Slave cylinder, who knows... you say you have checked everything under the car all you have left is the interior mechanical components. I say if it is bugging you that much get in there and figure it out.

I'm with this dude.

[87-325ic]

id love to, but i dont know how, ive never touched that area..

also, it is not clutch dependant.. meaning, it does nothing different wether the clutch is in or out..

[porsche gt1]

You say it is not the driveline, happens when the car is stopped or driving, the engine sounds fine, clutch in or out still happens. This has gotten rid of a lot of problems it could have been.

If you don't know how to get in the tranny, my best suggestion at this point is take it to a BMW mechanic and let him dig around to find the problem. Other wise it will be hard for us to help.

[87-325ic]

right, i was trying my best with you guys to narrow it down, so that if i couldnt figure it out with the help ive gotten, id at least have a well informed something to tell the mechanic...


can anyone tell me though, how this could hurt the flywheel? the actually torquing of the tranny output flange (170Nm) , while holding the crank bolt..

doesnt it generally recieve all sorts of forces in this range?

[DanielHStout]

Yep, just like I said I don't think that you fucked it up doing that.

[87-325ic]

i fucked something up for sure, its a Horrible vibration and i cannot even drive it due to not being able to rev past 2100rpm without engine/car ripping apart vibrations..

theres no way urethane tranny mounts would make this small preexisting problem into something so horrible would they?

i never noticed it before all this.. and i dont think just urethane mounts would make it this evident especially if i noticed nothing at all before..

[ZinRot325i]

My vote is on bad driveshaft.

Probably one or both of the U Joints or shot.
That or the CSB or the guibo.

[DanielHStout]

My vote is on bad driveshaft.

Probably one or both of the U Joints or shot.
That or the CSB or the guibo.

Dude, read the thread!

Man I don't know what to tell you. Swap the mounts and see what happens. Maybe the rubber mounts just masked your flywhell or pressure plate going to shit.

[MA325is88]

Is the engine skipping? Sounds it.