Alternator or Volt. reg?

[Bjurr]

I've got 2 quick Qs for you guys.

I've recently bought a 325IC and had issue starting the car on a damp day. After a quick check under the hood, I've found out the grounds where loose at the battery, and figured this is what caused the problem. Re-tighten, recharge the battery, next morning everything seems fine.

I had a few doubts about the charging system though, so just to be sure, I've checked the voltage when engine is running.

- idle gives about 13.25V
- around 1000rpm goes up a tad over 14V
- idle with headlights on drops at 13V / high 12V
- around 1000rpm with headlight would be around 13.5V

Reason I had doubts is that I can hear the heater fan speed drop when at idle. Never really noticed an intensity drop in the headlights though...probably because they are dirty as hell ;)

So, the questions:
- What would be the "acceptable" voltage range to expect on idle
- Upon closer inspection, bosch voltage regulator on my alternator says 1197 311 021. Every catalog/website I've seen says the part should be 1197 311 027. Anyone can confirm this?

I didn't knew much about e30's when I bought this one, and so far I've found the 325 IC to be somewhat the bastard child of the 325, so I wouldn't be surprised if the voltage regulator part number was different.

Oh, and yes I'm a newbie. My name is Bjurr, and I drive a 1989 alpine white 325IC :)

Thanks

[brandondan1]

My voltage regulator doesn't have a part number on the back of it. How else can I tell which one I need?

Thanks

[SpecM]

I had a few doubts about the charging system though, so just to be sure, I've checked the voltage when engine is running.

- idle gives about 13.25V
- around 1000rpm goes up a tad over 14V
- idle with headlights on drops at 13V / high 12V
- around 1000rpm with headlight would be around 13.5V

- What would be the "acceptable" voltage range to expect on idle

Thanks

voltage looks good, the fan speed drops at idle on mine too