Noisy Alternator

[FlyinRyan]

Hi folks,

I've been getting a loud humm from my alternator for the past few months. From my records the current on was installed in 2007.

Should I be going through it this fast? Can I do anything for the whine/humm?

Truck: '98 B2500 2WD, no AC

Thanks

 

[97ranger xlt]

Hi folks,

I've been getting a loud humm from my alternator for the past few months. From my records the current on was installed in 2007.

Should I be going through it this fast? Can I do anything for the whine/humm?

Truck: '98 B2500 2WD, no AC

Thanks

well i guess anything is possible. could be dry bearings. i had an alternator that had a high pitched screaming sound at certain rpm's. replaced it with a junkyard unit for $25. left the old one on the bench and it was completely seized when i looked at it again after one week...

just make sure it is the alternator that is making the noise. can be deceptive.
you could try running the engine for a short time in the driveway with the serpentine belt off.

 

[87ranger2.0]

Hi folks,

I've been getting a loud humm from my alternator for the past few months. From my records the current on was installed in 2007.

Should I be going through it this fast? Can I do anything for the whine/humm?

Truck: '98 B2500 2WD, no AC

Thanks

having an overly tight belt would cause the shaft to were the bearings out n cause a hummming noise.do you have alot of elec. In your truck bc that would cause over heating n bearin failure

 

[FlyinRyan]

The electrical system is stock, no AC and no mods.

My heater resistor pack is gone and the only fan speed I have is high... would having the fan on high for extended periods of time cause an overload on the alternator? Keeping in mind this load is present for months at a time in low (0C-> -20C) temperatures. I'm not willing to put a new alternator in until I get this heater thing fixed.

Any ideas??

 

[Bryan22]

take the 3 bolts out and have it tested. Alternators shouldn't be loud, and if you got a cheap one i wouldn't be surprised if it went out after a few years. also, no you having the fan up wont kill the alternator.

 

[FlyinRyan]

I bought the truck in 09, the alternator was replaced in 07, judging by the receipts I found. Would be the standard Monroe/Canadian Tire job.

Can I change the bearings? How can I test if the belt is too tight - it does squeak in wet weather.

 

[Bryan22]

just go buy a new one with a lifetime warranty change it and don't worry about it for a while....

 

[idriveafordranger94]

Your truck has an automatic belt tensioner, so the belt being too tight and wearing out the bearings is out of the question. Take your serpentine belt off and spin each pulley by hand to make sure it is the alternator that is making the noise. It could be an idler pulley or tensioner pulley instead. If you can't hear any noises by spinning each pulley by hand, use a stethoscope and while the engine is running, put the rod on each "accessory" (power steering pump, alternator, water pump, etc). You will definitely hear the one that is bad. Be careful not to get the cord (or hand) caught up in the belt or fan!

 

[FlyinRyan]

Your truck has an automatic belt tensioner, so the belt being too tight and wearing out the bearings is out of the question. Take your serpentine belt off and spin each pulley by hand to make sure it is the alternator that is making the noise. It could be an idler pulley or tensioner pulley instead. If you can't hear any noises by spinning each pulley by hand, use a stethoscope and while the engine is running, put the rod on each "accessory" (power steering pump, alternator, water pump, etc). You will definitely hear the one that is bad. Be careful not to get the cord (or hand) caught up in the belt or fan!

Tried doing this today... And I can't get the tensioner loose. How tight should it be? I got it to budge a bit but not far enough to remove the belt.

Is this normal?