So it appears my 184k mile 2005 MCS may have just destroyed the harmonic balancer. The car has always had a stock pulley and had the supercharger serviced 10k miles ago. It has a DDMworks Cold Air Intake and MSD coil pack & spark plug wires. Everything else on the motor is stock. I had planned on selling the car but had no interested buyers, so I am now thinking I'm just going to address the issues and keep it around as a toy/spare vehicle.

If it turns out to be the harmonic balancer, I have some questions:

1. Is the ATI harmonic balancer worth the extra money over a stock unit?
2. Is Way Motor Works' 2% ATI balancer worth the slightly even more money?
3. What else should I look into addressing while the car is being repaired?

 

I just replaced my balancer / crank shaft pulley on my 2006 R53 JCW with the ATI for the same reason- the stock one ate itself, neatly separating into two halves like a fork-split English muffin. Threw the P1688 code, burning rubber stink under the hood, AC promptly stopped working, and charging issues. Finally limp-home mode, thankfully only a few blocks from home.

This at a measly 55K miles on the original motor. I don't track the car, gentle driver, nothing aggressive aside from the occasional freeway entrance ramp spool up. Regular oil changes and nothing but premium high-test gas.

From the limited research I've done on the subject (here on NAM and YouTube, namely Mod Mini's channel) the original balancer / pulleys are a weak point in the Gen 1 motors. The vulcanized rubber inside just doesn't hold up over time. So, no, replacement with OEM quality solid model looked like a waste of time and money to me. There is the ATI and also the SFI after market brands, both are fluid filled and available on a number of sites - MiniMania, Amazon (which is filled by MM), Jegs, and Summit. I went with the ATI for expediency, as the SFI one, while $100 or so cheaper, wasn't going to be available right away as it was on back order.

to replace it if you need the help.

 

The PRW balancer is a good option too. A good bit cheaper than the ATI

 

Bottom line is, that the ATI (which is solid) and PRW which is fluid filled and balanced, are much better than the OEM.
Not sure about the PRW, but the ATI is a lifetime purchase which will never need replacing and can even be swapped or resold to be used in another Mini.
A replacement OEM will break again, no question.

As far as 2% over or not, I'd stick with stock diameter, belts are easier to figure since they are the same as stock, and if you want more power, do an S/C pulley change instead, extra boost is the only reason to go with the +2%.

I'd swap the pulley tensioner and chain tensioner as well, for strictly PM purposes.

 

The ATI is actually a weight inside that moves to balance as it is an inertia damper.

I've used and installed all the different brands of crank pulleys and can for 100% say the ATI is the best. Many times just installing it we notice the MINI idle smoother right off the bat. I don't use any other brand in my shop.
https://www.waymotorworks.com/super-...ulley-r53.html

Now if you have a JCW I think the 2% larger ATI is a really great idea as it will work with the JCW pulley to give you just a hair more boost making it the better option for the JCW car.
If you have a stock or JCW supercharger pulley you just use the same belt you are using now.

When you do it it's always a good idea to do the front crank seal and the crank bolt as it's supposed to be replaced each time you remove it.

 

A disturbing read for "Bargain Mini" with 155K on the clock and what looks like an original Mini balancer.

With the big miles I was having a hard time justifying $300 plus for aftermarket as appealing as they sound. I found an OEM rubber type with a 10 year warranty on Amazon for $97.30.


We'll see how that works out.

robj