'90 348 TS Alternator Issue

Sorry, but at this point it could be just about anything. The most important thing (to me) would be to make absolutely certain that the noise ISN'T coming from the timing belt, or from its tensioners.

There is no reason why the alternator shop should not have been able to repair your alternator so that it would last for at least a couple of years. If your car is a 1990, it probably has the Delco alternator, easy to overhaul. It may have been retrofit with the Nippondenso alternator.

As an aside, perhaps this is an indication of why a dealership would not want to remove and rebuild an alternator, as opposed to replacing it. Remember the "raccoon" 348 incident? The dealer insisted that they would only replace the alternator, which required upgrading the car to the Nippondenso unit, available only as a kit with new alternator, belt, bracket, and harness, at a cost of about $5000. The problem on that one turned out to be in the harness in the first place, so the whole issue was a fiasco for the owner. The dealer doesn't want to see comebacks.

 

I remember the raccoon incident quite well. It set me to wondering...to cook a raccoon of say 20lbs, how long would you leave it on the manifold at 3000rpm? Does it need to be turned?

 

As far as other possibilities for the source of your noise, we have seen a few instances of cracked alternator brackets that allow the belt to come loose. And of course, if the locking bolt isn't tightened after adjusting the belt tension, it WILL back off and loosen the belt.

It shouldn't be hard to diagnose the source of the noise, but there may be more than one problem (a belt problem causing the noise, and an electrical problem causing the light to come on).

 

15 minutes then 5 minutes per pound. No need to turn it but your gonna need some seasoning. Recommend a garlic blended onion salt and tarragon.


Seriously though...The VR is a $10 part (through channels other than Ferrari) that should have been replaced during the initial rebuild. I know why the dealer is at a loss, something doesn't smell right. Was the battery tested...perhaps a ground across cells or a direct short someplace on the car? (just a guess)

 

I've had my alternator rebuilt and fail within 48 hours because of diodes going bad on the bridge rectifier. Make sure the guy who is rebuilding it is using heavy duty components and to test the darn thing before they install it again.

As for the noise, belt not tightened properly? Bracket cracked? Bearing starting to get spun on the back of the alternator? It could be many things.

 

I rebuilt mine myself using parts taken from a thread here 15k ago & its been fine.The lite was coming on at high RPMS.Try it out,sometimes you have to do it yourself )

 

Since you have the Delco alternator, and your car is a '90, I'm assuming your battery is located in the left rear of the engine bay? If it is, have you checked the bullet connectors under the airbox? Those have a tendency to loose their "grip" and don't maintain good contact = battery light comes on. So have a look at those and then get back to us.

As for your "whistling sound" check all of vacuum lines on the plenum. Make sure they are all hooked up, and in good shape. No cracks or splits.

 

LOL!!!

 

Good advice. Better yet, take the factory cable out. Buy a new 5' cable. Cut the connections off the old one, slip off the factory plastic insulator-cover, slide it over your new one, heat shrink a couple of pieces on each end, and put it back in. Looks original, takes about 2 hours (I work pretty slow) and forget about the bullet connector.