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This vexes me...

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!!!!
 

Kaajot

Micro Machine Manager
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!!!!

Speculating, but wiring harness/ground out from alternator to wiring harness sending bad signals to CMD (computer) causing excessive rotation on alternator to produce more voltage (screeching) but no effect due to ground out lowering your voltage output to 10.2. Alternator's are new, so output from wiring harness? Are you testing 10.2v directly at the alternator plug or down the wire further away from the unit? Somewhere 4 to 5 volts are being removed, and most outputs are 5v in the harness (such as the MAP), so ground out in harness causing loss of volts.

Speculating...
 

Kaajot

Micro Machine Manager
Any luck with your voltage issue, Frank?
 

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