Alternator bearing?...squeal from dead stop plus...

[gogriz91]

Car has about 180-200 miles on it after an engine swap, took it out tonight for a spin, at a stop light while accelerating I heard the belt start to squeal.  I figured, "just need to tighten it" but it kept squealing and another noise which I assumed was the belt rubbing on something happened because I started to smell burnt rubber.  This went on for about 20-30 seconds or so then stopped.  Next light, squeal when launching plus what seems like potential grinding which dies out at about 15 mph, no squeal when accelerating at speed.  Brought it home, won't squeal just revving in the driveway but it looks like the belt is slightly misalligned to the rear at the alternator.  Alternator adjustment bracket has burnt rubber residue on it to boot.

 

Is this the alternator bearing, it's a non-AC car, a belt that needs tightening, get a replacement belt?

Edited April 26, 2015 by gogriz91

[Zed Head]

Take the belt off and see how the bearing feels.  Check the water pump also.  It has a bearing.

[gogriz91]

I will do that.  I also have a H.O, alternator from Z Specialties and it says it requires a special belt, I emailed Oliver asking for the replacement belt part number.

[Zed Head]

One thing not thought about often is that it takes torque to spin the alternator as it produces power.  So that 120 amps needs a good tight proper belt to avoid slipping.  It could be that simple.

[gogriz91]

I hope so, thanks for replying.

[Diseazd]

I had the same problem with a new alternator once. It would peg the amp meter all the way to the right. I installed a new alternator and voltage regulator. Problem solved.......not sure which did the fix. Steve J could probably explain why it pegged at max amps. It had that same burnt rubber residue and smell and squeal. If I recall, there was a fried wire in the voltage regulator. If you have a voltage regulator, take the cover off and check it out. I'm not sure if the alternator caused the voltage regulator to fail or vice versa.

[S30Driver]

When you remove the belt, see if there is a manufactuer name & part number on it

[gogriz91]

Update, went to the local Advance Auto Parts and asked them to check the electrical system.  Tester says the battery's got 100% charge but is bad?  Said the diodes are working in the alternator but that the voltage regulator is bad.  Wondering if I need to call Oliver and order a replacement HO alternator...

[Zed Head]

Some of the people who run those machines don't really know what the test is telling them.  They just hook it up and read the display.  Did they test it on the car or each individually?  If you have two components testing bad in the same system, you may be getting one affecting the other, giving erroneous results.

[gogriz91]

On the car, hooked up to the battery terminals.

[Diseazd]

Update, went to the local Advance Auto Parts and asked them to check the electrical system.  Tester says the battery's got 100% charge but is bad?  Said the diodes are working in the alternator but that the voltage regulator is bad.  Wondering if I need to call Oliver and order a replacement HO alternator...

I think he's probably dead on. The voltage regulator is shot and it's stressing the alternator. Too much drag will burn the bearings up. Mine did the same thing........same squeal, burned up the belt. The alternator got so hot I thought it was going to catch on fire.

[Zed Head]

So if the battery is fully charged but reads as bad, that would probably be incorrect voltage.  A dead cell maybe (6 x 21 V each).  A dead cell would show 10.5 volts (5 x 2.1), but no current flow.  And the machine might read the 10.5 volts as bad regulator.  Might also be why the alternator is working so hard to charge, pumping out full current and making the belt slip.

 

If you have a meter you can measure battery voltage yourself.  While stopped and with the engine running.  It will give you more details than the pass-fail of the parts store tester.

 

Not disagreeing with Diseazd,we posted at the same time.  But I would fix the battery first and then make sure the alternator is really bad.

Edited April 26, 2015 by Zed Head