I am totally vexed!!! Ever since I finished my 351 swap, I have had this belt squeal problem. I have new idler and tensioner pulleys, smog pump eliminator pulley, new water pump, new power steering pump and pulley, plus a new belt. When I start the engine, the belt screeches and the alternator doesn't show a charge. It'll read 10.2 volts. Now I can pull the alternator plug and the screech goes away. Or I can use my battery charger and while the engine is running, move the selector switch up two clicks from 2 amps/trickle charge to 40 amps and the belt screeching stops and the voltmeter will read 14.6 volts. I have replaced the alternator three times(new units, not reman) and this time I even tried replacing the voltage regulator to a soft start unit and still have the same belt screech problem.....I'm really lost at this point..please help!!!!
@frank5079 So even after charging overnight, the battery still only has 10.2 volts ? I don't understand how you are only reading the alternator output and not the battery that just started the engine ? A fully charged battery should show around 12.8 volts. Anything over 15 volts when the alternator is producing power is bad. Anything under 13.2 volts isn't enough to charge the battery and run your accessories. Check the power cable going from the alternator to the battery, it may look good but have a bad crimp or corroded connection ? Also check the ground cable at the engine to the chassis and the engine to the battery.