Hey guys,

So I've been driving around my GFs 03 R50 trying to replicate some electrical issues she has and today while driving to work, the ABS light came on as well as the traction control light (tire pressure light also went from blinking to solid as I have a donut on it and dropped off the rim to get a new tire mounted 5 minutes before this).

Noticed that i lost power steering and i saw some of the gauges flickering figured i finally replicated the issues she's been talking about. Get to work, shut the car off, try to start it again and dead battery. At this point I assume its the alternator since that would explain no PS and the dummy lights coming on with low voltage.

Let the mini sit for 4 hours, go outside with a DMM and see the battery voltage is around 11.9V, start the car up and its hesitant but starts, and check the voltage at the battery, 10V and dropping so i know its not getting the charge.

I looked at Rock Auto and saw that there are 3 different current outputs for the Mini, 105, 110, 120. I'm going to order the 120A model but wanted to make sure there's no known issues switching between the outputs or if there's anything else I should check before confirming its the alternator.

 

Check your crank pulley, too. They are known to come apart and it drives the main/alternator belt. It usually sets off a bunch of dash lights when it goes.

 

Thanks for the heads up! The alternator has less than 300 miles on it since it was installed ~2 years ago (long story) so I'll check the crank pulley when I pull it or even just change it anyway since it looks like its when not if they go

 

A dampened pulley like the ATI or fluid filled PRW are usually recommended.

 

But back to the amperage, I'm assuming I can go 120A with no issues?

 

the amp rating is what it CAN put out .... you will not over power the system ... the excess just charges the battery until full . . . and then is wasted . . . with my '79, when you begin to have electric issues one of the first things to do is up the output of the alt' .... with the "standard" output alt' when I try to run upgraded headlights (halogen and angel eye), the wipers, and the heater fan (defog the windshield) my car can't support 'em all at idle speed ... everything slows or dims. When I had to replace the alt' I SHOULD have gone to the higher output model ... now I know.

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if the battery is more than 3 years old I'd replace it ..... today's batteries do not die slowly or gracefully .... in part because you are not really cranking the car when you turn the key (or push the button) ... you just tell the computer to start the car .... and when voltages or amps get low, especially close to minimums, weird things happen . . .

 

Thanks guys, I'll pick up the 120A if it is indeed shot. Now, onto the harmonic balancer. I'm a bit confused. I'm not looking to spend a ton of money on this so I'm not going to go with a high performance one, but does the R53 pulley fit the R50? And if so, do i need a different length belt or anything?

 

Make sure you have checked all connections at the alternator and to the battery from the alternator. Could be as simple as a loose connection.

 

I've seen the PRW for around $240-$250 and the OEM for $270-$300. The PRW Fluid pulley is supposed to perform better, outlast the factory pulley, and is cheaper in cost. Maybe a vendor can give more feedback on the pro's and con's of each.

 

I'm hesitant of spending that kind of money right now as I'm trying to determine if this mini has a BC1 failure. If that's the case, I may be spending $$$ to begin with. The problem I have is I'm not "allowed" to work on vehicles at my apartment so when I pulled the front end off on a Saturday morning, it needs to go back on right away. With the mini having 88k on the clock, I think it's safe to assume it'll need a new pulley so maybe I should just order this expensive one anyway

 

On the R53, the crank pulley can be changed just by removing the front wheel. Maybe the R50 has the same access? Also, maybe your crank pulley is still good. I was just giving another possible cause of your issue because it wasn't determined if your alternator was bad, especially since you said it only had 300 miles on it.