My truck never had the stock alternator, so I never really paid attention to the post about adjusting them. Now, I am using a stock M715 alternator on my M35. I installed and wired up the 1967 GE Prestolite alternator yesterday.
The previous owner told me it over charged and just needed adjustment. I had everything but the exciter wire bolted in like it should be. Fired up the engine, checked voltage with a digital multimeter as 22.5. (One battery almost dead and the other more dead.) Aligator cliped the exciter wire to on and that thing kicked in. The idle speed dropped, it started to whine and 30.8 was the output voltage. I screwed the Allen head screw at the back all the way and all the way out. Nothing changed.
Does this mean the regulator is completely shot and need replacement? Is there another screw to adjust? Does anybody here have regulators for sale?
There is no hurry, I have another alternator to try and a complete truck to rebuild before I actually need it.
Thanks.