Originally Posted by tomw0
Have you removed the serpentine and spun the alternator armature by hand? You should be able to feel any roughness in the bearing while it is in place.
Additionally, you can get new bearings and install them into your current alternator. It is not difficult, actually.
It is easy to de-grease the bearings if you cleaned the engine compartment. You would then notice more noise and possible squeaks and chirps. If you do take the alternator apart, you can squeeze grease beneath the seal, and possibly leave the originals in place. But, you want it to be smooth as butter when you get done. Any roughness will amplify over time.
yes I did my best to spin the alternator the fan drive bearing water pump etc.
So far I found the Fan drive bearing to be noisy and I replaced it along with the fan clutch that was worn also, the alternator is slightly rough I have heard worse even the water pump seal sounds dry when spun by hand.
however since I replaced the bearing for the fan drive and belt the loudest noise sounds like it is coming from the alternator.
I may end up replacing the water pump also.
Yesterday while running the engine while it was cold the engine was quiet except for the alternator it had a bit of a whine which got louder and louder as is warmed up then eventually it sounded like a knocking sound.
yes I did wash the engine bay down and the engine but I covered the alternator however It is still possible some cleaner made its way to the bearings in the alternator.
when I get my new alternator I plan on taking the old one apart to see how dry the bearings are.
I purchased a new alternator not a rebuilt one
in the past I have rebuilt alternators yet my new one was cheap enough that is wasn't worth the added work on this truck.
I think the new belt and new belt tensioner has applied more torque to all the pulleys which is why I think the alternator noise is so much louder now.
what is driving me nuts is the sound is very similar to a rod knock
but at this point even if I have a rod knock once I get all the other noises fixed I will have to do something about it
I found a rebuilt engine at Rock Auto for 1750 or so plus a core charge and shipping. if I end up needing it I will just drive the truck until it gets much worse., or sends a rod through the side of the block.
once I get the alternator in and water pump if needed I plan on connecting a oil pressure gauge tot he engine and checking out the pressure.
I noticed my oil pressure immediately goes up instantly to around the half way mark or a little higher while cranking, it happens almost too fast. like someone grounded the circuit with a resistor to fake oil pressure.