I was reading alot on here how to install an SC pulley and it seems its being WAY OVER COMPLICATED. This weekend I was able to remove the pully quite simply and with out the use of a puller as everyone is saying.

I used whats called attention to detail. Once I got the mounts off and jacked up the engine to access the pulley I noticed 2 smooth bore holes (not recessed) centered in between the 6 alen head bolts. EVERY pulley that Ive seen those on were self removing with out the need of special tools.

First, you remove all the bolts with the belt tensioned.

Second, you take 2 bolts and place one in either hole of those smooth bore holes. Start to turn them and you find that its threaded on the back side.

picture of the symetrical smooth bore holes



Third, remove the belt.

Forth, tighten the allen bolts evenly alternating one to the other. The pulley gently slides off and this process pushes back the clamping pedastol on the back side loosening that too. there is no deformaion in the pulley and didnt need to use anything more than an allen head socket for the ratchet.

picture of the threads on the back


the most damage to the OEM pulley set up


So am I just missing the thread that points this little trick out or did I stumble on something. This pulley came off a 2003 MCS all factory no after market parts... unless some one slipped this by me as an after market pulley.

 

Very interested to know ....

 

After looking at some pictures of pullies Im 100% sure that this is not factory. It came on the car and Im pretty sure the previous owner new nothing about it. I have no clue what modle or company makes it. It was replaced by an ALTA 15% pulley while i was replacing my AC compressor.

It I origanly deleted this when I could not verrify what pulley this was, but apparently it came back... hmmm There is a disctinct diffrence in the SC sound and power so Im guessing this was just an aftermarket or light weight pulley. Im pretty clueless as to what it could be. Im new to the mini world.

 

You're correct that the pulley in your pictures is an aftermarket unit. Here's what the factory one looks like:



As you can see, there are no extra holes or other features on the stock pulley. It's installed at the factory by pressing it onto the end of the supercharger shaft with a hydraulic press, and has to be removed with a puller.

That's really interesting that you noticed a big improvement with your new 15% pulley. I don't know who made your original pulley, but all of the aftermarket ones I can think of are at least 15% overdrive. There's not really a market for a stock-diameter lightweight pulley, because the weight of the pulley is so small compared to the weight of the supercharger shaft that just using a lighter pulley that's the same size as stock wouldn't give you any performance gains. Perhaps your old belt had started to slip. You *did* put on a new belt when you replaced your pulley, right?

 

I am definately not new to builing and maintaining cars by any means. The first thing I did was run a compression test, change the plugs, new wires, coil, belt, oil filter, oil. While I was at it i replaced the floppy rear wiper arm and blad, front blades, torn leather shift and brake boot. I try to get most of the misc easy wear parts replaced and since I was doing the AC compressor I did the pulley and belt at the same time. I dont trust what the other person sells me.

Did a quick once over made a list of items that need to be replaced as well. Looks like the tierod ends, all the motor mount/rubber, sway bar bushings (new bars), the rubber bellows are cracked, and the suspension is on its way out the door. I also had the dreaded 03 ignighter problems. Been working for the past month with oenxenonparts.com with little success. They dont have a listing of compatability so they are swapping BMW parts and hoping they fit. The OEM ignighter lead is about 11" long. They sent me one from a 3 seris that had a 3" lead (which didnt even warrent opening the light). The longest they have is from a 7 series adn thats only 6.3" long.

Im eyeballing hotchkis sways,all new bushing/ mounting components, and got a set of megans comming in.

As for the noticable diffrence, not realy going by the but dyno. Its more acceleration under similar conditions, the tires are breaking loose a tad sooner (RPM wise) under similar straight line acceleration situation and getting a little more push ithrough the turns than previous. It seemed to dog a bit exiting the turn prior to the pulley. After it, its definately got more pep. I wouldnt put a number to it but slightly more noticeable. I wouldnt say its the greatest mod ever but Ive wasted more money in the past and got worse results. LOL

 

I guess your previous aftermarket pulley could have had less than 15% overdrive, although those are rare. Going from a stock pulley to even a 15% gives a *very* noticeable improvement, and is by far the best "bang for the buck" horsepower improvement on the first-gen MINIs, especially if you do the work yourself.

 

If the prev owner was going "back to stock" to sell, there are 0% pullies and the ones I've seen look like the one you pulled. They are easier to install since they use the same mounting mechanism and no press needed and they look like a 15% except bigger...

 

I guess I should clarify, my feel for the cars preformance is honestly a little skewed. Got rid of a fiarly built car and im use to that one so the hypothetical 20hp on the mini is enough to get my attention but I didnt put any credance in it because I didnt see results on a dyno. I just notice more responce over the previous pulley.

And I just want to say now, please ignore all the spelling and syntax errors. I've been doing statistics home work and computer programing for classes the past 11hours.

 

The pulley in your pics that you removed looks to be a helix pulley, as for what size you will have to measure it, they are not labeled. If you noticed a change in sound it must be a different size than what your new on is, or it's the placebo effect.

 

That and maybe a new belt...
sounds like you just wasted about $200 on a new pulley when you already had one..
Looks like a helix....sold in 15, 17 and at one point a 19...(the desgin is kinda unique).
so you either put the same size pulley on, or reduced your performace with less reduction.
the oem pullet is a hot pressed steel pulley..no bolts.
At one point a few odd sizes were floating around, mostly machined in eastern europe...so a few jcw sized ones were around..oem replacent........Size...ever seen/heard more than a rumor.....