Engine vibration w/new motor mounts
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Hello
Just got my shark back today with fresh motor mounts, and to be honest I'm a little dissapointed
Every post I've read says it really smoothes things out, night and day difference etc.
On the road moving I can tell a difference, not a huge one, but it does feel smoother when you get on it, with less vibes overall.
This is what bothers me though...At idle, the car still shakes. Its pretty subtle and low frequincy but you can still feel it in the seat, and throughout the whole car.
I know some vib is normal with this big v8 in a 20yo car...But how much is normal?
My MM were collapsed, and the new ones raised my engine back up, so atleast I know they did put new mounts in.
Thanks for the help
Parker
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Just got my shark back today with fresh motor mounts, and to be honest I'm a little dissapointed
![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
Every post I've read says it really smoothes things out, night and day difference etc.
On the road moving I can tell a difference, not a huge one, but it does feel smoother when you get on it, with less vibes overall.
This is what bothers me though...At idle, the car still shakes. Its pretty subtle and low frequincy but you can still feel it in the seat, and throughout the whole car.
I know some vib is normal with this big v8 in a 20yo car...But how much is normal?
My MM were collapsed, and the new ones raised my engine back up, so atleast I know they did put new mounts in.
Thanks for the help
Parker
889285SPD
#4
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Parker,
Were you using a Jager Speedmount before you put in new motor mounts? I was underwhelmed by the transition from Speedmount to new motor mounts, so that might explain something.
I have slight idle vibration in my car, too. Maybe new trans mounts would further help smooth things out.
What kind of MMs did you use, by the way?
Were you using a Jager Speedmount before you put in new motor mounts? I was underwhelmed by the transition from Speedmount to new motor mounts, so that might explain something.
I have slight idle vibration in my car, too. Maybe new trans mounts would further help smooth things out.
What kind of MMs did you use, by the way?
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Just a thought - if they were Porsche hydraulic they could be already partially collapsed after sitting on the shelf. If they were aftermarket hydraulic same could apply. They would give the effect of raisng the car but settle back down after use as they have no water in them.
Blip the throttle and see if your engine rocks side to side - if it does I would say your MM's are fine and you need to look somewhere else for resolution.
Blip the throttle and see if your engine rocks side to side - if it does I would say your MM's are fine and you need to look somewhere else for resolution.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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Hey
Chad, I went with the Porsche mounts, after much debate, thats all I'm going to say about that one
. The mounts were not totally collapsed like others posted here, but definatly in need of them long ago.
Thx guys for the other ideas. My idle dosn't fluctuate much, maybe 25 RPM? Engine runs pretty smooth as far as I can tell.
I did replace the front shifter coupler, which really did wonders in tighting up my shifter. Also vibrates more now, than it did before too. So maybe some trans mounts are in my future huh?
I can definatly live with it the way it is now, I was just a little pissed when I got it home and everything wasn't silky smooth. I apprettiate you guys chiming in, it always makes ME
feel better to have some idea whats going on with my Shark than not!
Thanks
Parker
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Chad, I went with the Porsche mounts, after much debate, thats all I'm going to say about that one
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Thx guys for the other ideas. My idle dosn't fluctuate much, maybe 25 RPM? Engine runs pretty smooth as far as I can tell.
I did replace the front shifter coupler, which really did wonders in tighting up my shifter. Also vibrates more now, than it did before too. So maybe some trans mounts are in my future huh?
I can definatly live with it the way it is now, I was just a little pissed when I got it home and everything wasn't silky smooth. I apprettiate you guys chiming in, it always makes ME
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Thanks
Parker
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Originally Posted by ROG100
Blip the throttle and see if your engine rocks side to side - if it does I would say your MM's are fine and you need to look somewhere else for resolution.
Thats the first thing I checked when I got home, definatly rocks. Pulls to the left maybe an inch or two when I give it throttle, then back right when released.
Thanks
Parker
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#8
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to see if the mounts are collapsed look and see where the bottom of the oil pan is in relation to the cross member with good mounts the oil pan should be almost flush with the crossmember with collapsed mounts you will see the pan sagging below the crossmember
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ahh forgot to add you might be ready for a set of plugs and wires, if your feeling something rough while the engine is running
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hello
Thanks for the suggestions...
Mrmerlin and Garth, the mounts look good, plugs, wires, and all the tune up stuff I could do was done a year or so ago...
Injectors were pretty far down on my to do list, which seems to be never ending
. will give them a look...
Too bad you can't just plug in a diagnostic tool, and be done with it!!
Its about time for that beer or two
Cheers
Parker
889285SPD
Thanks for the suggestions...
Mrmerlin and Garth, the mounts look good, plugs, wires, and all the tune up stuff I could do was done a year or so ago...
Injectors were pretty far down on my to do list, which seems to be never ending
![grr](https://rennlist.com/forums/graemlins/cussing.gif)
Too bad you can't just plug in a diagnostic tool, and be done with it!!
Its about time for that beer or two
Cheers
Parker
889285SPD
#13
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Originally Posted by ParkerC
hello
Thanks for the suggestions...
Mrmerlin and Garth, the mounts look good, plugs, wires, and all the tune up stuff I could do was done a year or so ago...
Injectors were pretty far down on my to do list, which seems to be never ending
. will give them a look...
Too bad you can't just plug in a diagnostic tool, and be done with it!!
Its about time for that beer or two
Cheers
Parker
889285SPD
Thanks for the suggestions...
Mrmerlin and Garth, the mounts look good, plugs, wires, and all the tune up stuff I could do was done a year or so ago...
Injectors were pretty far down on my to do list, which seems to be never ending
![grr](https://rennlist.com/forums/graemlins/cussing.gif)
Too bad you can't just plug in a diagnostic tool, and be done with it!!
Its about time for that beer or two
Cheers
Parker
889285SPD
Injectors are just one of the possibilities - and may be low on the priority list. One can always toss in a can of injector cleaner ( Techron, seafoam, ...) - on the basis that it can't hurt, easy to do - and sometimes helps.
#14
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Originally Posted by Garth S
Injectors are just one of the possibilities - and may be low on the priority list. One can always toss in a can of injector cleaner ( Techron, seafoam, ...) - on the basis that it can't hurt, easy to do - and sometimes helps.
#15
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Yes the fuelinjection system may need a clean out stop and go driving short runs with the engine being shut down then restarted after a few hours lets the cleaner work better than putting in a can and going for a long drive.