I have recently noticed that my r53 is making a sort of rattling or metal on metal screeching noise at high RPMs. 5200+, and the sound tracks with the RPM. I don't hear it at all before then. It just sort of starts around there and increases in intensity if I don't shift up.

I have installed the DT bypass valve already but my fuel injectors and camshaft (listed in my sig) are still pending.

I noticed the noise after installing the BPV but it's possible that it isn't related (may have been happening before, not sure). I mainly noticed it recently because the weather is nice and I have been driving spiritedly and with the windows down.

It's possible that it's a hose clamp that's vibrating. Or maybe a loose bit that wasn't properly tightened during the BPV install. Or something else. Or maybe my supercharger is out of oil (although I did service it about 2 years and 20k miles ago).

My car has about 125k miles on it, gets fluids changed and checked regularly, runs perfectly otherwise, and isn't giving me any other signs of trouble. Detroit Tuned didn't have any suggestions when I emailed them earlier.

Until I figure it out, I'm trying not to rev it too high. I'll do what I can to get in there and figure it out soon, but I wanted to see if anyone had experienced this and had some ideas to guide my troubleshooting or possible quick fixes.

As always, thanks very much to this community for the help and advice!

 

Iv seen threads titled "rattle of death" with supercharger as subject, im sure someone else with more knowledge will chime in.

 

Death rattle eh? Well that is not super encouraging.

If it's the S/C, I'll see if I can get some more life out of it by changing the oil again soon.

If the S/C goes, I guess I'll just have to spring for the aftermarket one. Tragic...

 

A metal screeching sound would make me suspect either the idler pulley or the pulley on the belt tensioner.....the bearings in either one could be failing. That’s where I’d check first. Both are relatively easy repairs. Check them by releasing tension on the belt and spinning both. If they are hard to turn, super loose/wobbly, or make noise, then they are toast.

 

Ah, now there is something I wouldn't have thought of. Thanks for the insight, I'll check into that.

 

With those miles don't leave out the crank pulley.

 

I have a 2 percent ATI super damper waiting to go in, along with a new belt. Saving it for when I install my cam and injectors so I only have to get in there once.

Looks like I'll also be checking tensioners and servicing my supercharger.

Hopefully this thread generates a good amount of stuff for me to take care of all at once so that my car is right as rain once I finish my installs. Keep the suggestions coming!

 

I had a belt tension that was doing that......and like others have said, I would check the SC...and crank pulley/balancer.



Can you have someone get in the car and hold the RPM's up while you listen up under the hood? Should be easy to find.

 

If it IS in fact your supercharger making that noise, no amount of "servicing" is going to fix it. You are going to have to send it out for a rebuild, or just buy a rebuilt one to put on it. Once you have metal on metal contact of the rotors, or bearings.....it's done.



Changing the oil isn't going to do a thing except waste your time and money.

 

Well I guess I will cross my fingers and hope that it's something stupid like a clamp or simple like a tensioner. I'll try poking around in there while having someone work the throttle.

How difficult is it to rebuild a supercharger? Could I buy a kit and do it at home?

If I have to shell out the cash for a new one, I'll buy a an upgrade. Not really trying to dump another three grand into this thing but I'm sure the extra power would feel nice.

 

Nope....rebuilding a supercharger isn't really a DIY type of project.....it's not like you are just replacing seals, there is a lot more to it. And at the rpm those things spin combined with tight tolerances.....it's a pretty specialized job that needs specialized equipment and skills.

As far as upgrading.....what would you upgrade to? Just remember....if it's an aftermarket SC of some type, you will also have to have the car tuned in order to get it to run right....and that's not cheap either. If it was me, I would just find a quality shop that sells rebuilds and go that route....

But like you said, hopefully it's something easy like a belt tensioner.

 

If I find it's something simple, I'll do the simple thing no problem. And I am hoping for that. The car is already plenty of fun to drive.

If, however, it's my supercharger going out, I would probably get the Sprintex S5-210. It's not much more than a stock one, pricewise. And coupled with my 19 percent pulley, 2 percent super damper, WMW race cam, and JCW injectors would probably make a lot of difference. (I also have aftermarket I/H/E.)

I already have to go get a tune once I finish my installs (cam/injectors/damper, which I'm waiting to do all at once this summer as time permits), so throwing a supercharger upgrade in wouldn't really affect me.

This car is something of a money pit for me, but I love it. Once it's "done" this summer, I'm hoping to be putting out more power than the top end new models.

 

I haven't really heard much about the Sprintex....except that not many people have them I could be way off, but I thought they were closer to $3,000 while a rebuilt oem SC is around $700-$800 ish.

I wish they had more aftermarket supercharger options for our cars....

 

I was just looking at one for 2500 new online (first thing that popped up for a search of "r53 supercharger upgrade"). I know Mini Mania sells them, and they were 3k last I checked there almost two years ago. Not sure of the reviews. But you're right: I don't know any that have them. Honestly, I don't know anyone personally that mods their mini. Which is crazy, since there's a ton available. And my car just keeps getting more and more fun.

But now I am derailing my own thread.

 

Silly question.

I don't know why I didn't think of this before (except I guess it's been a while since I put it in) but there's only one tensioner on the Mini engine right?

If so, I have the Alta fixed one, which I know isn't super high on everyone's list for various reasons. Guess it's possible that's loosening. I will need to check that out. The more I drive it and try to listen, the more believable that seems.

Thanks again for the input, all.

 

Wanted to give this thread a bump with (what I hope is) the resolution to my query.

While I guess it is still possible that my S/C is on its way out (125k miles with only one oil service about 15k ago), I do believe my problem was actually the ALTA tensioner. When I had my cam/balancer/injectors put in, the shop said that thing was vibrating all over the place. They took it off.

Since then, my car is still super loud under load (because of all the parts), but I'm 95% sure I'm not hearing that same rattling. If it's there, its so quiet compared to all the other racket that I can't tell if I'm imagining it or not.

So, to summarize, the ALTA tensioner is probably not worth it. It'll be fine for a while and then crap out. Stick to stock.

Hope that's helpful to anyone experiencing something similar.