how much VIBRATION is normal?

[stueveone]

Hey guys,
So my Rabbit vibrates pretty bad at idle. I attributed it to it being over 26 years old and a diesel. But then my buddy who used to own a diesel way back when took a ride with me and kind of made a big deal about mine vibrating badly.

So, how much vibration is normal?
Diesels ARE going to vibrate more than gassers right?
What are some possible issues to address to curtail some of the vibration?
I've heard that the front strut assembly is one area, and possibly injector timing, what else?

Thanks,
stueve

[duffer]

Motor mounts

[hagar]

try adjusting idle speed.

Fraulein Bunny Bondo is Smmmmmmooooth reduse the fuel a little at the same time.

hagar.

[tylernt]

If you put a hard object like a pen in your glovebox and it dances, chances are your passenger side motor mount is broken.

This mount is a pain to replace, too... requires removal and re-timing of the injection pump, as well as an 8-ton hydraulic press to replace the mount inside its bracket (I was lucky and got a local machine shop to press it for a few bucks).

Playing with the idle speed can help, a little...

I have a new mount and I still have some vibration at idle, definitely more than a gasser. However it's not objectionable and the pen I keep in the glovebox barely rattles now.

To help keep my mount from breaking again, I deleted my A/C compressor (that thing is heavy).

[stueveone]

All of my motor mounts are brand new. If I put a pen in the glove box it dances all right. I'll have to check and see that the mount is tight, maybe it loosened up since I put the engine back in.

[tylernt]

I had a mount pressed crooked and it failed within a few hundred miles.

Also... are you sure the passenger or trans mounts were put in right-side-up?

[Fatmobile]

I put a passenger side motor mount in upside down once and the vibration was bad.

[stueveone]

I pressed the mounts in myself. I put in the new ones like I saw how the old ones went in. But for kicks, how can you tell they are in right. And how can you tell if the mount is failed? The rubber is broke? Well, I'm glad it's my car and not something else!
Huh, I guess I'll have to inspect around a bit.
But so that I've got the shooting straight :

-check mounts
-check Injector pump timing
-front struts? I know for a fact that mine are cashed, just wondering if this is actually a possibility.
-idle speed adjust

[tylernt]

My short-lived crooked mount was only rotated a few degrees... so alignment is pretty critical. The passenger side one should look like a guy standing on his head in the installed position. Not sure about the trans mount... I bought one but haven't gotten around to doing it yet.

I could tell my passenger mount broke, because the round metal part of the bracket was no longer flush with the two "ears" or thick flat rubber discs that go on either side. The mount was sunken below them between 0.25" and 0.5".

If you didn't retime your pump with a dial gauge after reinstallation, then the vibration certainly could be timing.

I've never heard of struts causing vibration when the car wasn't moving.

Anyway, bumping the idle speed up would be the first thing I tried.

[3Bunnys]

You don't mention the year of your bunny... I've been through 5 bunnys and they've all had there "vibration issues"....... The later cars were a lot smoother, I suspect VW made some changes and some stiffening to bodies that is not readily apparent.
Part of the problem is bunny bodies are resonate ...VW did any number of things over the years to help (band aid) the situation. I had an 82 with a spring mass (chunk of steel on the end of a flat bar) bolted inside front bumper. I've noticed that my 83 has a big chunk of metal (another spring mass) attached to the clutch operating shaft where the clutch cable attaches. One of my bunnys has a piece of broom stick between the tunnel (between front seats) and roof to keep roof from resonating. Of course the whole dash board rattles at idle. As does the rear trunk lid, the rubber bumpers back there are hard as rocks and don't do there job anymore.....
All of them run nice and smooth once I put some RPM's on them,,,
regards R

[stueveone]

Yeah. Mine runs the same way. Smooth once some idle is on it. Once the engine warms up, it tends to run more smoothly as well. I'm not going to worry about it. It's still a good idea to time the IP though.
Thanks guys!