MA7008O

Yesterday I was putting bat together the car after cleaning the intake system and found out that the A/C pulley attached to the crankshaft is loose.

It moves freely in and out of it’s location and it can be turned by hand with no hesitation.

Questions are:

- Is this normal? (really doubt it)
- Is it reparable or do I need to buy a new complete pulley?
- Can it be changed with engine on or do I need to lower it?
- Any other advice on the matter?

Thanks a lot.

ThomasC2

The pulley is really two pulleys bolted to the third/inner pulley with 10 or something allen bolts. Are the "whole" pulley lose from the crank, or is it just the two outer pulleys?

The whole pulley package is torqued to the crank with one bog bolt and 235 Nm.

Hopefully you can just bolt it back on with the allen bolts or the center bolt...but on the other hand, if these are lose you may have an other problem. Let us have some more info!

You can work with the pulley if you remove the rear engine mounts/carrier and support the engine from beneath.

MA7008O

The two pulleys for the fan/alternator seems to be OK; it's only the third pulley (A/C one) the one than is loose.

No sings of loose bolts or marks, but I really not sure; I am not able to look at the center of the assembly to see if there are any of the blots.

What other problems may I have if bolts are lost?

Any inputs on the Engine vibration damper? I think that maybe bolts are OK and that the problem is at the vulcanized rubber ring (number 3 on picture).

Indycam

Your vibration damper has given up the ghost .
#3 is no more .
#3 has expired
#3 is an ex
'E's bleedin' demised !

Google
Dale manufacturing .
$89.00 plus shipping .

MA7008O

Thanks for the input, but it's going to be hard to get it done the same day from Spain... Sometimes I wish I 'll still be living in the States.

Just got the pulley out; let's see if they sell it alone, the price, ... or may be I'll have to find someone that will repair it locally. Does the position matters in any way?

MA7008O

Just seen a picture of on pulley that has 1 small hole; mine has 3.

I imagine that it's for balance, but, how would I ever know where those hole must be????

Are there any marks to know the relative position between parts???

Thanks again.

ThomasC2

The complete 3-part pulley is balanced as a unit. so if you mount a new outer pulley I guess you have to balance it again as a new unit.

Indycam

The position can be "seen".
The crank and inner pulley are pinned
The pulley has a tdc #1 mark .
Set the crank to tdc #1 via the piston touch method .
When the crank has be set to tdc #1 , put the outer pulley on so the the tdc Z1 lines up .

ThomasC2

I understand that this is the mounting procedure, but will this also handle the balance issue?

MA7008O

Some news:

- Spoke with local dealer and they sell the 3 pulleys as a part for 1.000 euros!!!!!!!!
- Going to talk with a local shop that works with vulcanized rubber to see if they ca put it back together.
- The 2 alternator/fan pulleys has not been removed, so it's position with respect of the crankshaft is not a matter.
- Since the A/C pulley has been removed, I guess balance is an issue. Is it?
- Do I need to remove the alternator/fan pulleys when the A/C one is repair to balance the complete assembly?
- Thomas: what other problems were you talking about? Balance?
- Indycam: what do you mean by "When the crank has be set to tdc #1 , put the outer pulley on so the the tdc Z1 lines up".

Thanks again.

ThomasC2

I told you it was expensive!!

My only question is how you get the correct balance in the pulley if you try to put it back togehter. Because Porsche did balance every pulley-pack before it was bolted to the crank shaft. You can see some drilled holes/pits on the outer pulley and they are done to get it exactely balanced so those pits are in differrent places on every pulley out there.

I don't know how you can do this the right way. I just know that it is not a good idea to put an unbalanced pulley to the crank when it suposed to help the crank with the balance.

Hopefully somone else can help out here.

Strange fault this one, never heard of it before.

MA7008O

It's not expensive; it's a theft!!!!

My car did not have A/C and I installed when I bought it. I tend to believe than an old pulley (16 years old) with no stress suddenly has to work may be the issue about the failure.

Now about the balance; here are my reflections.

- Crankshaft is rotating and the end of the A/C pulley is balanced; no problems.
- If pulley is not balanced (after been repair), it can alter somehow crankshaft balance.
- A/C been connected does not have to make a difference on balance of the pulley or crankshaft themselves, but it must cause some modifications on the axial load on bearings and so on.
- I believe that the text on the image says that the mass of the 3rd pulley counteracts the vibrations on the crankshaft.
- I really doubt that only the mass of the 3rd pulley can balance the crankshaft especially when it is balanced separately.

- Where am I getting? Really, no idea, but something tells me there is something else.

Hopefully I’ll have an answer by Monday as to wherever the pulley can really be repair, and the I must ask some other shop specialized in racing engines to see what they have to says about it.

Meanwhile, SOME ONE COULD HELP!!!!!!!!!!!!!!!!!!!!!!!

Rocket Rob

Have you considered buying a used pulley from a dismantler? I'm not sure if there are any near you but there are several in the US that specialize in Porsches.

http://www.partsheaven.com/
http://www.dcauto.com/
http://www.911pcar.com/
http://www.germanautodismantlers.com/

No affiliations and good luck on the repair.

Edit: The last one has the pulley listed as in stock. See http://www.germanautodismantlers.com...00_c_4626.html

MA7008O

Thanks for the input, but I don't think that it would be a good idea to buy an used part that fails due to a rubber component.

The used one would have as much time as mine and chances are that it would also fail.

Indycam

Yes .
Putting them back in relationship will .

But if the inner and outer are off a few degrees ,
the balance might be a bit off a little .

I think it all has to do with how well the job is done .

The pulley can be sent out for a test / rebalance .