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-   -   Bad vibration? (http://forums.pelicanparts.com/showthread.php?t=691930)

Dane Brown 07-31-2012 12:56 PM

Bad vibration?
 
Ever sense I got the car it has always vibrated bad up to about 3500 RPMs then smooths out. The vibration is so bad it sounds like a constant bass from a sub/speaker. It sets car alarms off sometimes if they are sensitive. I was just wondering if anybody knows why this is happening, and how to fix it. Thanks.

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gwrinkle 07-31-2012 01:20 PM

Sounds like balance shafts or belt for the same.
Gary.

9FF 07-31-2012 01:23 PM

Your lower balance shaft is 180deg out.

Dane Brown 07-31-2012 01:35 PM

How do I fix that? And where is it located?

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Dane Brown 07-31-2012 01:47 PM

Dang..I just looked it up, that's not a quick fix at all. I hate messing with the timing belt it scares me. I have been luck enough to where I have never had to mess with one.

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9FF 07-31-2012 02:21 PM

It's a common mistake but an easy fix. Line up all the marks, loosen belt, rotate lower balance shaft roller to correct position, tighten belt to spec.

Dane Brown 07-31-2012 02:59 PM

How long do you think the job will take?

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John_AZ 07-31-2012 03:06 PM

Dane Brown.

Have you had time to check your clutch disc.

Your post:

http://forums.pelicanparts.com/6828825-post24.html

Vibrations at 3000 to 3300 are caused by the rubber clutch disc breaking apart.

http://forums.pelicanparts.com/uploa...1343772264.jpg

John

Dane Brown 08-01-2012 02:54 AM

Is there a way to check that without taking the bell housing off?
What's the most easy way to check for that john?

John_AZ 08-01-2012 04:59 AM

One of the ways to check is to remove the starter and poke your fingers into the hole to feel for small chunks of rubber or coarse rubber like dirt.

Clarks has a clutch disc thickness test. Use a deep well socket that fits tight in the space and measure the socket to make it easier.

Checking Clutch Disc Wear

If your bell housing is missing the rubber inspection cover you can buy it on Pelican . 931 116 177 00
Pelican Parts - Product Information: 931-116-177-00-OEM

If you do not find bits of rubber and the clutch disc measures OK, the clutch may still be vibrating if the PO-previous owner did not have the FW-flywheel surfaced/machined or the FW and PP pressure plate is out of balance.

Check the mentioned BB balance belt pulleys to make sure they are correct on the shafts.

http://forums.pelicanparts.com/uploa...1343822260.jpg

The shaft keyways are the dark spot on the top of the BB shaft.

GL
John

Dane Brown 08-01-2012 10:20 AM

Also I don't know if I specified that the car vibrates bad at idle but the motor runs great. Idle is at about 700 RPM And stays at that, It vibrates the most when only driving at very low speeds and around 1500 2000 RPMs even with it in neutral it vibrates.

Gawernator 08-01-2012 12:21 PM

700 RPM is really low?? Mine idles from 900-950.

Dane Brown 08-01-2012 01:58 PM

Never mind yeah mine is about 900

kfanazini 08-01-2012 09:13 PM

Motor mounts.

John_AZ 08-02-2012 06:23 AM

Quote:

Originally Posted by kfanazini (Post 6889010)
Motor mounts.

Double +1 ^

Dane,

When you buy MM motor mounts, do not buy the cheap ebay "Deutsche Parts" or URO.

These will last less than a year before you begin to feel the idle vibration start again.

The best are OEM Porsche. Rein MMs are great but they stopped production. So unless you can find new old stock--hard to find.

Meyle is an alternative, Not the best but so-so.

If you look on ebay for used, a few sellers will list the "left" or drivers side used.
WHY? because the passenger side (right) fails first due to the heat of the exhaust manifold.

Only buy OEM Porsche left used if on a budget (if you want to replace only the passenger side).

Motor mount "collapse" when bad.
You can check your MMs per Clarks

http://www.clarks-garage.com/pdf-manual/eng-11.pdf

GL
John

9FF 08-02-2012 07:40 AM

When my MM's were bad I could only feel them at idle, rubber centered clutch is normally only in the 3k range only. The op says he has vibration from idle to 3500 that is typical of balance shaft 180 out. Smooth as silk above 3500, vibration below that.


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