1986 not charging.

[csjackson41]

So I have changed the alternator/voltage regulator, checked the alternator to starter fuseable link(I think it was the right one. I cannot figure out why it’s still not charging. Any ideas?

 

[adsm08]

Check the green/red wire for power with the key on.

 

[csjackson41]

Check the green/red wire for power with the key on.

Thanks I’ll give it a shot

 

[RonD]

1986 should use an Amp Meter so is a little different

Key off for these tests
On the back of alternator is B+ wire terminal, should have 2 Black/orange stripe wires attached, test voltage on that terminal using Alternator's metal case as the Ground, should read Battery Voltage exactly
If battery reads 12.5volt then thats what you should see

Unplug 2 wire connector on alternator
Yellow/white wire should also show battery voltage, exactly

If there is no voltage then on any of these then Fusible link is bad, all 3 wires use same fusible link

If either doesn't show battery voltage exactly then test again using battery negative terminal as the ground, if voltage changes then you have a bad engine ground, check negative battery terminal for corrosion and cable on the engine

Light green/red wire, with yellow/white wire, should show battery voltage but only with key ON, it can be slightly less voltage, .1 difference
This wire is the ON/OFF switch for alternator, it provides Startup voltage needed so alternator can startup, an alternator would drain the battery with key off unless it was wired this way, so it needs "Key on" 12volts to startup.
On newer systems this is the Battery Light wire

If all voltages test OK, then start engine and test battery voltage again, should show 14-14.8volts
If still at "12.5v" then test voltage at B+ again, if its also at 12.5v then new alternator is bad


The AMP meter is connected to the Black/orange stripe wire at 2 places, with 2 wires, it measures about 10% of the AMPs running from alternator(B+) to the vehicles systems, so it shows + if amps are flowing TO the vehicle and battery, and - if amps are flowing from the vehicle and battery to alternator(not charging), if one of these wires was disconnected it would also show -