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alternator ?

4K views 30 replies 7 participants last post by  acardon 
#1 ·
my 57 was converted to a 3 wire alternator---not charging battery---previous owner installed new wiring but i dont think they are connected correctly--- the 10 gauge wire from the batt terminal on alternator and smaller black wire from the alt plug are run together to the starter solenoid and are joined together with the black wire connecting to a small terminal on the solenoid--i cant figure out why the black and red were joined at that point and why the red wire wasnt connected to the batt terminal on the solenoid or run directly to the battery---can i disconnect the red batt wire from the alternator and run another 10g wire directly to the battery without hurting anything the way its wired now i dont think im getting any power to the batt---checked alternator ---putting out 14+
 
#2 ·
my 57 was converted to a 3 wire alternator---not charging battery---previous owner installed new wiring but i dont think they are connected correctly--- the 10 gauge wire from the batt terminal on alternator and smaller black wire from the alt plug are run together to the starter solenoid and are joined together with the black wire connecting to a small terminal on the solenoid--i cant figure out why the black and red were joined at that point and why the red wire wasnt connected to the batt terminal on the solenoid or run directly to the battery---can i disconnect the red batt wire from the alternator and run another 10g wire directly to the battery without hurting anything the way its wired now i dont think im getting any power to the batt---checked alternator ---putting out 14+
Yes, the red wire from the alternator output should go directly to the battery terminal of the starter solenoid. The #2 terminal of the small plug can also go to the battery terminal of the starter. The #1 terminal needs to be connected to the small brown wire that was on the generator.
The body needs to be grounded to the engine.
 
#29 ·
after un wrapping the tape from the big alternator wire i found the smaller red wire that came out of the alt plug was taped to the big alt wire but before it got to the starter it wasnt connected to anything---just taped to the big red wire---should the smaller red wire also connect to the starter soleniod---i hate to be a-pia- but this one of the last things i have to do and i want to get it right
 
#5 ·
alternator

first of all tks don for your replies-----checked all wires --appear to be correct --two wires coming from the alternator going to the batt terminal on the starter solenoid---alternator reads 14+ but nothing appears to be going to the batt --reads just under 12---- voltmeter reads just under 12. im stuck
 
#6 ·
first of all tks don for your replies-----checked all wires --appear to be correct --two wires coming from the alternator going to the batt terminal on the starter solenoid---alternator reads 14+ but nothing appears to be going to the batt --reads just under 12---- voltmeter reads just under 12. im stuck
With the engine off, read the voltage at the alternator output terminal. It should read 12.+ (battery voltage). If not you may have a blown fusible link or bad connection.
 
#10 ·
There should not be any fusible link (or anything similar) between the alternator, starter (solenoid battery terminal) and battery. Only the large battery cable to the starter and a large wire (10 GA) from the alternator to the starter.

Any fusible link should only be between the power source (solenoid battery terminal) and the wire going to the under-dash harness to prevent electrical fires in the car.
 
#11 ·
Most aftermarket wiring harnesses have a fusible link at the starter to the alternator wire, to protect against a melt down if the alternator wire shorts out against a pulley, exhaust pipe or is pinched someplace on it's way to the starter.

For 100 amps, I think you need a blue fusible link.
 
#19 ·
How many amps is your alternator and what are the loads on it?
 
#25 ·
The reason fusible links are used instead of fuses: A fusible link is a slow reacting fuse, so a momentary overload will not cause it to open where as a fuse will blow instantly. This will allow a brief 100 amp load (full field) to pass, before the wire it's protecting can heat up. If the load lasts long enough to heat the wire, the link will blow. Using a fuse of the correct size to protect the wire connected to a potential higher amp alternator could cause lot's of fuse changes.
 
#26 · (Edited)
I think you are thinking too hard. Neither of mine have ever blown. I can't remember how long it's been. But if you are one to work on the main power fused to and from the battery without disconnecting the negative cable then shorting something out, knock yourself out and use a slo-blow type maxi fuse or a mega fuse like they use in modern cars.
 
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