20FHK02

For those of you who plan to install the ASP pulley yourself: I found an alternative way to loosen the belt tightener pulley without even touching its fragile torx head!

I busted the torx head for the one on the S/C belt loop and had to replace the whole belt tightener assembly ($60). Upon doing so, I found something very informative and wanted to share:

Pry out the plastic cap on the tightener pulley using a flat-head screwdriver; this exposes a 15mm bolt. Use this bolt, instead of the torx head at the end, to loosen the pulley. A standard 15mm long socket will do. I also used a pipe extension and the far right air filter box bracket to hold the "loosened" pulley stationary so that it was a lot easier to put on the belt! See the attached pic for details.

The worst that could happen on using the 15mm bolt is you might loose the bolt by applying too much force. This is not a problem at all, just retighten it and try again, much better than deforming the super ductile torx head!

rrf

That looks like the way it was supposed to be done all along.

Many thanks.

20FHK02

I know! If you look at the top pic closely you will see that the torx head for the pulley was "rounded"! I have absolutely no clue on why the smart engineers at MB would decide to use such a tiny AND soft torx bit to drive that super stiff pulley...

20FHK02

Actually the methodology is applicable to the tightener pulley on the A/C loop also. But this pulley is in a relatively open area so if you have the E10 torx socket you don't need this trick. But if you don't have the right tool this trick will surely help!

madryan

how long did it take for you guys to install the pulley??

Buellwinkle

A little over an hour because I had to take pictures and take notes for the instructions I put together. Also I didn't have someone elses instructions to go by. It's not that hard, just a matter of removing parts and putting different ones back on. No magic, just nuts and bolts! If your car is fairly new you won't even get your hands that dirty.

20FHK02

I had the ASP pully backed on last night and just checked the underneath cover pan: it still leaks!!

I used fine sand paper to smooth out the steel ring surface, applied grease as instructed, and even used torque wrench to get it to about 100 ft-lb (I know Lee suggests 85 but that sounds kinda low).

Dang! Guess my car really hates the pulley...

mctwin2kman

Your seals around the pulley may be slightly worn, I would have them replaced and then install the pulley. Also take a visual inspection with the car running. Get under there and see if you can see it wobbling around at all, and you may be able to see where the oil is coming from.

20FHK02

C230Jeff:

Did you really torque it to 220 ft-lb? I think this is the spec for the steel stock pulley, but the strength for the aluminum ASP pulley is a lot lower than steel.

When I put back the stock pulley last time I also only torqued it to 100 ft-lb or so and it did not leak. Anyway, an under torqued pulley might fall off later, but 100 ft-lb is a pretty strong force to create a tight contact already, so I don't think the torque strength is the cause of the leakage.


mctwin2kman:

The think only leaks when it is under load. If you leave the engine running at idle it will not leak. And when I put back the stock pulley it did not leak.

avlis

I'd replace the seal and see what happens. It's the only thing other than the pulley that would cause a leak.

Yeah, yeah...why doesn't it leak with the stock pulley? I don't know but, mechanical seals sometimes have a funny way of interacting with different seal surfaces. They "get used" to the mating surface then leak when that surface is changed.

I would also suspect that the seal surface of the new pulley is too rough (you said you sanded it). It should be polished to 32 microinches or better.

Matt230K

I torqued my Kleemann pulley to 220 ft-lbs. and have had no problems whatsoever with it (except belt rubbing). But I don't know how the materials differ between the Kleemann and ASP pullies.

20FHK02

Vadim: what did you torque your pulley too?

mdp c230k

220ftlbs will cause an aluminum pulley to deform! This is possibly flaring out the part of the pulley that is against the oil seal. take off the pulley and inspect it for cracks caused by over torquing it then put it back on with half that torque.

20FHK02

I do not know how smooth 32 micro inches looks like. I did sand the surface using 1000 grid to a shiny reflective finish. But it is still slightly rougher than stock so I might sand it a little more later.

When I take off the pulley again I'll also take off the seal (if doable) to check for damage.

If everything fails, I will give up and conclude that my car really hates aftermarket pulley.

Matt230K

mdp, are you talking to me? I'm not having any leaks, so I kind of think I should just leave it alone. Will it damage anything besides the pulley?

I should talk to my guy at Kleemann and see what they recommend.

Matt230K

Well, i just wrote after you that I put my Kleemann to 220ft-lbs. So I didn't know who he was talking to. I don't want to take mine off either. That could cause more problems.

avlis

Why do you have to remove the pulley to re-torque the bolt?

Matt230K

The suggestion by mdp c230k was to remove the pulley to check for cracks or deformation and then reinstall. So that would require removal.

gab

20FHK02:

hey you wanna sell the pulley to me or try on my car? I live in the south bay also

mdp c230k

Actually, I was talking to both Matt and Jeff. At 220ftlbs there is a good chance that a stress crack will develop on the pulley. It might take some time but it most likely will and when that baby goes watch out! The place to look is where the key slot is cut into the pulley as right angles are weak spots. If there is no sign of a leak yet then you might get away with just backing the bolt out and retorquing to 100ftlbs. Use some Loctite to hold the bolt in place rather than over tightening. It is the key that prevents the pulley from spinning, not the bolts tightness. The bolt keeps it from coming off the crank. Hope this helps.

Mark

20FHK02

OKay, I went back to my textbook and here is what I found:

The typical elastic modulus for steel at room temperature is about 30E6 psi, and 10E6 psi for aluminum. This indicates that the stiffness for steel is roughly 3 times higher than aluminum.

So if 220 ft-lb is the safe zone torque for the steel pulley, it should be 220/3 = 73 ft-lb for the aluminum ASP pulley, since the same bolt and washers are used providing same bolt parameters.

The elastice modulus is lower at higher temperatures when the engine is hot, so over torquing the ASP pulley is very dangerous in the long run.

So Lee's suggestion of 85 ft-lb is already on the high end. I think the machinest should know what he is doing so I trust his recommendation.

Matt230K

I think those with ASP pullies should do what those here suggest. However, with the Kleemann, I asked and 220 ft-lbs. is how tight it should be. The part where it bolts to the crank is actually steel.

20FHK02

Both Kleemann and ASP pullies are aluminum. The steel is only a steel ring at the end. On the outer end against the bolt head/washer it is still aluminum. So the outer end still could be over deformed.

mdp c230k

Is that T6061 aluminum? Thats what they are using to make the pulleys. Thanks for going the extra mile I didn't have the time to do!

Buellwinkle

Yes, T6061 for both ASP and Kleemann.