Bobdole

after reading all the post on the sheared off pulley,i'm thinking if this car had a harmonic dampner it could of prevented this from happeneing.the question is on a 2002 c230 is a harmonic dampner necessary,and i do drive my car hard,and canyon runs at least once a week.i know this topic has been drop up b4,but no accidents have reported till now.any insight would be great thanks

Buellwinkle

We may never know why this one pulley failed and saying it's the dampener is as good as anyone's guess but consider that Kleemann sold solid dampenerless pulleys for the older C230K sedans for 6 years without incident, the chances of it being dampener related is slim. The one scenario is that this pulley failed for being overtightened as there are about 30 in the field some with over 10-12k miles and no failures including mine with 7,500 miles, the other is that the aluminum hub is not strong enough for this role. If you have a concern with you pulley write to ASP and ask them what's going on, it's your right, asking the forum won't get you that answer, just fuels competitors into a feeding frenzy.

Outland

I can see several scenarios for the failure:

1)Overtightened- metal may have deformed unevenly. Deformed metal doesn't hold a clamp load. Doesn't look like this is the case thou...it didn't spin around the bolt...

2)Design flaw- metal around the steel sleeve simply too thin. This is the most likely, based on what little I know.

3)Manufacturing defect- ring of material around the sleeve undersize, the bore could have been off center, or tilted, causing the pulley a lot of stress when rotating. Part could have been misloaded during one of the machining ops, making certain features off location.

4)Defect in the Stock...porosity in the area where the hub meets the pulley could have created a weak area.

5)the Dampener...maybe it does need to be there. I find this the least likely scenario.

I hope Jeff gets his car fixed, for as little dough as possible...what a rotten experience to have, eh?

mdp c230k

We have gone over this without any final verdict. My vote is that the damper must be there, period. If MB uses it so should you. Do a search and you will see all of the reasons for having the damper I have listed with references. Just because it functions without one does not mean that it functions as designed without one. Play it safe and smart unless you are the gambling type, do you feel lucky? If you want more info pm me and I'll fill you in. Several people in the engine design field in this forum have also said the damper is needed. Not one person that extols the virtues of the ASP pulley is qualified in any way to be reguarded as an expert. Choose wisely, it is the engine to your car!

Buellwinkle

mdp c230k, assume for one short moment you are correct. Then wouldn't you also agree that modifying the factory pulley by adding a ring to it would require that the pulley be rebalanced. Afterall, it was properly balanced by it's manufaturer as parts of the pulley are drilled out to balance it. I know the pulley is balanced and the ring is balanced but combining the two together does not equal balance, hence the s/c failures we've seen with this type of configuration. Also the dampener was tuned for a certain size/weight pulley, wouldn't it alter the frequency if you change the weight? So ideally, it's best not to replace this pulley at all. Why not work on getting a smaller S/C pulley? The safety factor is much better (not attached to the engine), the costs are dramatically lower and this is an accepted practice outside the MB arena. As a side benefit, it may fit the 1.8L.

mdp c230k

A round ring will not alter the balance of the pulley if the ring is balanced. Remember the ring balances around the same center as the pulley and adding uniform equadistant mass will not alter the balance of a spinning object around a center point. The damper will not change in frequency as the damper does not change in mass. Once again, remember that the harmonic damper is seperated from the pulley by rubber so it is not effected by the addition of the ring. The harmonic damper damps the crank motion not the pulley motion so it still is working as it should. The damper quells the twisting of the crank on first cylinder firing and without it the twisting force is sent to the pulley and everything else on the belts. Maybe this caused the failure? I might look into a s/c pulley but it is harder to remove and replace and smaller diameters can throw off a belt more easily. More food for thought.