Bosch W0133-1605336 alternator

[alittle1]

I have a 98 Camaro 5.7L with a Bosch alternator, may battery will run down overnight from a fully charged NEW battery to 8.46v. I pulled each fuse to find the parasitic draw and it was still drawing 2.4v. I know pulled the alternator. How do you go about checking the Bosch alternator? Is a diode gone? Do you have a rebuild procedure on these like the CS144 and 130's? Thanks, enjoy your rebuilds, ED.

[Randy]

Yes, you have bad diodes in your bridge rectifier. Diodes tend to degrade in that they wear out like tires. When they are new they work great, as they are overworked they wear out and don't pass current as well, or as in your case, they no longer act as one way gates for the current. They start to pass current in both directions which causes power to go to ground. As you may know the wire connected to the battery post on the back of the alternator has power to it at all times, if a diode shorts out it will drain your battery dead.
I'm sorry but we do not have repair video on the Bosch alternator yet, but we will have an online manual soon.