P1sc head unit pulley rubbing main bracket

[7Lemons]

I have a procharger stage II kit that I purchased (used) and installed over the winter. I've worked out a couple small problems with boost leaks, belt slipping, and coolant burping. The car has been (and still) runs like a champ. I hit 11.5psi @7k rpm reliably. I know these non helical gear P1SCs make some noise at idle, however lately I've noticed a new noise and it seems to be my main pulley (which is a 4.00) rubbing or scraping the main bracket. I don't know where the pulleys came from, the used kit came with 4 pulleys. I can see metal shavings from the pulley in the area. Any ideas on what I can do? I haven't had it apart yet to see the back side... is it possible to put a small flat washer in behind the pulley or does the way it mounts prohibit that? Otherwise the head unit seems fine performance-wise) and I can't see shaft play when it's spinning or anything. Also, I did loosen the pulley bolt and tried to re-seat the pulley just enough to get about 1/32" of clearance and tightened it back down and it seemed not to rub for a while after that, but now it's back to rubbing. Here are a couple pics, thanks for any help.

 

[slow306stang]

That's either the wrong pulley for the application or it's on backwards. The coyotes need a "standard" pulley with the hubs being equal on both sides

 

[7Lemons]

That's either the wrong pulley for the application or it's on backwards. The coyotes need a "standard" pulley with the hubs being equal on both sides

Thanks for the reply. I looked at the other pulleys and assuming they are the same type the hubs are equal on both sides. Could there be a spacer or something missing on the inside? Know where I can source an authentic ATI 4.00 pulley that's the proper size/type for the p1sc? I didn't see it on procharger online store... brute speed here says "standard, slight offset" does that mean the standard one does have a slight offset maybe? ATI DPxxx ProCharger Pulley 6 Rib and 8 Rib


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[apex svt]

If I remember right there was a spacer ring on the last procharger I installed(Marine application). Looking at the belt marking on the idler it looks like it could be pushed out. Notice any odd wear patterns on the belt? I’d try to contact Ati, but the last time I did they were just shy of useless.

 

[jeffs]

Make sure your head-unit is tightened down good against the bracket, That's the only thing in my mind that can change, unless you just changed to this pulley, and then hears a new sound. If all else is good, and the belt seams to be tracking straight, I'd have a machinist cut down a little of that pulley where it's meeting your bracket.

Call beefcake, or email him the pictures you posted. Maybe that pulley is supposed to be flipped, and that nose could go towards the head-unit, and would certainly gain you clearance.

 

[7Lemons]

I did indeed check all the head-unit bolts and they are tight (I added loctite too when I installed). I thought about having it machined down although it's now self-machining against the bracket As for the "nose" it is equal on both sides so nothing to be gained by flipping it. I looked at the other pulleys from the set and there is no offset one way or the other - it's perfectly symmetrical. I think I'll call ATI today and see what they say. Although, like apex said, out of the last couple times I called them, one time the guy was agitated to even be on the phone, and the other time the guy couldn't really help me. Maybe this is straight-forward and they have a spacer or something...?

 

[slow306stang]

@7Lemons - i'll take some pics and measurements of my blower/pulley/bracket setup when i get home today.

 

[7Lemons]

@7Lemons - i'll take some pics and measurements of my blower/pulley/bracket setup when i get home today.

Ok thanks, I'd appreciate that. What are the keyways for in the pulley hubs where the bolt goes through - is the bolt keyed somehow? I wish I could see how they mount in general without taking it off. I guess it's time to take it off though and see what I have goin on. I found some hits searching around about shims on the backside... hmm..

 

[7Lemons]

Nevermind on the keyway question, I see now the SC shaft is keyed and you put a key into the slot of the pulley/SC shaft. Talked to ATI - it is supposed to have a .150 shim on the backside. I don't know if I have that installed on there or not since I left the pulley on that the previous owner had on there. He said it should have been on there, but when he looked up my head unit S/N it turns out my head unit was originally for a different application (Chrysler 300), and that might be why it's not on there (if indeed it's not). If the shim is already on there, they make other sizes so I could potentially get a thicker shim. I'll post back what I find.

 

[Bill@HPTuners]

as stated you are missing the spacer ring, call procharger, I'm sure they'll sell you one for a few bucks. They look similar to this Pulley Spacers for ProCharger Superchargers

 

[7Lemons]

as stated you are missing the spacer ring, call procharger, I'm sure they'll sell you one for a few bucks. They look similar to this Pulley Spacers for ProCharger Superchargers

Thanks for the response - just looks like a stainless washer huh? Yep I contacted ATI, that's what I was saying in the post ^^^ there. ATI is sending me the .125" spacer. I just wonder if I already have the spacer on there. I can't tell from my pics. I'm guessing not, like you're saying. I'll find out tonight!

 

[Bill@HPTuners]

if its rubbing you likely don't have it installed, I originally had the issue as well(used head unit with the pulley removed) looked around and it showed up with one of the other pulleys that came with it. Your seller likely just forgot to include it or something.

 

[7Lemons]

Well I took it apart today and was surprised at what I found. I did have some sort of shim/spacer behind the 4.00 pulley - BUT it was curved on one side and flat on the other, and the convex surface of the washer/spacer is recessed INTO the pulley hub, and therefore it acts NOT like a spacer. Have you guys ever seen this before? So I have 3 other pulleys (see pics) and the other 3 don't have this recessed area at all (just flat). Depending on what ATI sends me, if it's flat on both sides, I can slip it behind this one and still use the 4.00 pulley. If not maybe I'll use whatever they send and try the 4.13 pulley and live with slightly less boost from that size. Another question I have is putting the key back into the driveshaft of the SC head unit. Does the key go into the groove/slot with the concave side up (like I have shown in the pic), or does the key get flipped? Thanks guys!

 

[MG0h3]

Typically any spacer will be flat/straight. I suspect something is sized wrong and the washer has pressure put on an area that bent it.

The surface of the pulley where the spacer rides appears worn. Is it possible that it was ran without the key, spun, and wore that surface down? This would place the pulley closer to the supercharger and bracket.

The more I look at it, the worse that pulley looks. It looks like some material was actually pulled over to where the key goes. I'd just order a new one and use the new spacer.

 

[7Lemons]

Typically any spacer will be flat/straight. I suspect something is sized wrong and the washer has pressure put on an area that bent it.

The surface of the pulley where the spacer rides appears worn. Is it possible that it was ran without the key, spun, and wore that surface down? This would place the pulley closer to the supercharger and bracket.

The more I look at it, the worse that pulley looks. It looks like some material was actually pulled over to where the key goes. I'd just order a new one and use the new spacer.

Holy hell I didn't think of that - maybe it didn't start as recessed at all and wore down like that..?? That's quite alarming if that's the case. It does make sense as to how it used to not make noise (that I noticed), and now it became noticeable and was grinding against the bracket. The key had to be in place though for it to be reliably and consistently building boost. This is one of the many downsides to buying used stuff - especially on something like this, I just don't know it's history. I am its 3rd owner. So - maybe the previous owner(s) didn't have the key in right at first or something? Speaking of the key, does it get installed like I have in the pic with the concave side out? Thanks...

 

[MG0h3]

Edit: can’t zoom in the pic but I see what I think you’re referring to as concave.

Is one side of the key more narrow, like a V versus just square on the other side?

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[7Lemons]

Okay - so opposite the way I have it in the picture. It does seem to fit tight into the pulley too. I'll ditch that 4.00 pulley and start with something known. Maybe I'll try the 4.13 pulley. I wonder what the difference in boost will be 4.00 vs 4.13? Maybe 1 psi?