I recently picked up a used KWSC kit from a FF member. Seller had explained that he had the belt snap on him twice before he removed the kit from his car. When I received it, pulled it out of the box, super dirty and oil residue all over it. When I hold it in my hands and spin the pulley about every three turns I get a tight spot enough that with the oil residue on my fingers I almost can't spin it.


Now I have heard that rotrex charges have a planetary gear set which apparently will have a tight spot. Can anyone else confirm whether theirs had a tight spot as well? I'm nervous that this may be from the belts snapping due to incorrect tension or misalignment and have bent pieces inside the charger. Or possibly this is normal and just needs to have some oil run through it.


I have experience with turbos but never have I dealt with superchargers, so I don't feel terribly comfortable pulling this one apart. Have heard of local shop here that is a turbo/supercharger shop that can inspect it and definitely have it cleaned due to it's atrocious condition.


Thanks for any help,


Guy

 

Is this on a idler or tensioner pulley or the Rotrex unit itself?

I have a C15-60 that I replaced with a fairly similar symptom that you're describing... To me it seems that my unit may have been ran low on oil and may have bearing damage from it. From what I also understand, during heating and cooling cycles the seals inside these S/Cs will of course expand and contract with the temperature change... Whenever the unit cools, the seal cools at a slightly slower rate and during this time oil seaps in and will be consumed during the next operation cycle.

I tried to tear mine down and inspect it but there is a slide plate inside that I couldn't figure out how to remove without destroying the unit. Its still interesting to take apart BUT just as a heads up you will likely not get everything disassembled.

 

Hootie, this is right on the rotrex unit itself. Yea I figured it may require somewhat of a rebuild possibly. Hoping I don't have to replace the whole unit itself. Is yours installed yet? I need some more information about the kit you might be able to help me with.

 

I see... Mine is not installed yet. Was pissed off after my initial attempt that the replacement Rotrex didn't come with a pulley mount holder and I needed up stripping the inner threads for the hex bolt. Some extremely foul words were said and I sent it off to get repaired since I didn't have the tools (or patience... or sanity) to do it myself right after that.

I was pretty much done with installing the hardware of the kit, just needed to do the S/C's oiling system. What's up? I may be able to help.

 

 

I actually had parts of the kit measured up for situations like this... I've been CRAZY busy with work, autocross, and personal issues to actual update and let the entire GD community know about this.

Give me a bit, I may be able to find the shop/person's e-mail.

Edit: The part in blue is the actual S/C pulley. I believe it is a 95mm pulley... currently thumbing through phone to make sure. I KNOW you can get it from Skunk2/Kraftwerks as a direct replacement part. Just specify what kit you have.

 

That would be phenomenal! Definitely had been finding it extremely difficult to get answers from anyone about this kit. Glad someone is current with this as well. Other question I have is belt length? I have one, shipped to me by previous owner at what looks to be about 1930mm. Don't know how much I trust that as he snapped two of them.


EDIT: here's a picture of a measurement of my pulley. As you can see I received it in PERFECT condition...





Cheers

 

The belt for the C15-60 or M/T kit is a Gates K100789 (C15-16 or A/T kit is unknown) that has had a few of the ribs trimmed off (to be made narrower) to fit.

 

Is that the same one you are using then?

 

Correct. I am using a C15-60 equipped M/T KWSC kit. I verified that the belt length was correct with the used belt that came in my kit which was purchased from dustinb on this forum.

 

The other thing I thought of was, if I can get the belt length at least close and if I need to purchase a larger mechanical tensioner. Replacing the OEM one that would be on the car.