TheSamba.com :: View topic - Random belt squeal and 16+ volt spike! (91 cabby)

Fri Jan 13, 2012 4:00 am

First of all, what up everyone! Long time no see!

Well, as the title implies, I have a 91 Cabby which has been puzzling me that last few days.

I'll just be driving along normally then suddenly I hear a squealing belt and the voltage meter jumps up to 16 volts. The alt may be pushing out more power than that but my volt gauge only goes up to 16! I'm sure it's not a false reading because all the lights suddenly get VERY bright when this happens and I get people flashing their brights at me, thinking I have my high beams on.

I've been able to get away with shutting off the car and starting it back up again, but that only works for a few minutes before the belt starts squealing again and the power jumps back up to 16+.

It seems to me that if the alternator belt were slipping then it would lower the power output, so I'm stumped here...

Any Ideas?

Today the belt finally broke, which leads me to think that the alt was somehow resisting rotation, but when I spun it by hand, it spun freely.

I'M BOGGLED!

Fri Jan 13, 2012 2:46 pm

When I first got my 87 years ago it spiked like that also. Lights went bright and volts were maxed out and made the squeeling noise. I replaced the voltage regulator with a Pick and pull one for a few bucks and got a spare. That cured the spike problem. If your regulator is on the outside mounted with two screws it's an easy job. Not sure what the 91 looks like. Check the bearings in the Alternator just to be sure.

Fri Jan 13, 2012 9:33 pm

It's a Duralast alt which supposedly has a lifetime warranty so I guess I'll try to just go change out the whole alternator tomorrow.

Thank you very much for the input!

Fri Jan 13, 2012 10:06 pm

If it has the regulator mounted with the two screws on the outside most reman ones dont come with a regulator. Make sure your parts guy does not install the old regulator on your new alternator if it does not come with one or you end up with the same volt spike. My alternator lasted another 10 years after replacing the regulator.

Sat Jan 14, 2012 4:58 pm

Well, after a short chronicle of idiocy between advance auto repeatedly selling me the wrong size belt, and autozone giving me hell with the alternator warranty, I've finally got this mostly sorted out.

I Just started her up after putting the new alt on (came with new regulator) and it seems to be doing ok.

Although there's still this issue which I've experienced ever since I've owned the car, and had the same thing with both ACVW's that I've owned...

When I start the car, I need to rev it up to about 2-2.5K RPM before the battery light goes out. Is this normal, or do I have more problems than I thought?

Sun Jan 15, 2012 12:19 am

Mine does the same thing with both the oe. bosch and the replacement one always has.

Mon Jan 16, 2012 2:33 pm

bookoojoe wrote:
When I start the car, I need to rev it up to about 2-2.5K RPM before the battery light goes out. Is this normal, or do I have more problems than I thought?

Normal; explained here: http://www.cabby-info.com/gauges.htm#start .