Inliners International Forums General Discussion Electrical I'm Not Charging

I have a 57 Chevy pickup (3100) with the original 235 engine. I just freshened up the engine compartment by cleaning and painting everything from firewall to bumper and the engine. It now has Offy intake with Carter/Weber progressive carbs, HEI, alternator, Fenton headers with glasspacks, and new Chevy Duty wiring harness made for 3-wire alternator.

My problem. Without lights on, the needle on the guage points slightly left of center towards discharge. If I turn the signals on, it moves slightly left with each blink. If I turn the headlights on, it moves left about an 1/8" off center. Without lights, I seem to be able to drive fine. Friday night I drove the truck about 15 miles with the headlights on and then stopped for a sandwich. After eating, the battery was not powerful enough to start the truck. I waited about 20 more minutes (about a total of an hour) and it had enough recovery to start and drive another mile home.

I'm pretty sure my wiring harness installation is correct. I checked every connection several times before leaving it.

How would you diagnose this problem? Thanks for your help.

Jerry

What alt. do have or running?? And how do you have it wired?? How about a Pick of the Alt. and Wiring to it ?

Dear Jerry;

Go to the Library & photo copy the (3 wire) diagram out of the Motors Manual.

You have to "feed" that Alt. from the ignition switch. The + (output side) goes to what was the Bat. on the old voltage reg. which goes to the ammeter.

The 'third' wire is/was for the light which you don't have.

Good luck.

If its a GM 3 wire alt. check the following:

1) the main output terminal is connected to the battery - if you have an ampmeter and you are having charging problem - run a wire direct to the battery and see if your problem disappears - this will bypass the ampmeter for testing.

2) the other 12 ga. wire on the 2 connection plug needs to be connected to the main battery cable, unless you have the battery relocated to the trunk. This wire is a sense wire for the internal reg. if the wire run for the main output terminal is long you will get a voltage drop and the sense wire compensates for this by increasing the output voltage.

3) the small 16/18 ga. wire needs to be connected in series with your charging idiot light, the other side of the light gets connected to the run position of the ign. key - its this wire that turns the alt. on/off.

Always use a voltmeter to troubleshoot an alt. installation.

Oh one other item.

If the battery is remote mounted then the sense wire needs to be connected as close to the battery as possible.

If you go to my signature link and go to the 'misc' folder you'll see a picture of the alternator and wiring. Thanks for your help.

I just looked for it. It takes 30 minutes for it to be visible to you. Sorry. Check about 11:30 EDT.

The two wires Can Be looped Then once the rpms are over Idle it should sart charging your system. I have the same Alt On my 64 SS Chevy2/Nova which had a ext. Reg. I made the Loop for the old wiring(reg). and a Loop for the Alt. and it charges Just fine. Follow what efi. is telling you and you should be Just fine.

Ps. I'm also running Auto Meter Gauges Which are mounted Into My Steel dash.(custom Dash) Hum i knew i was missing a Pic on my new site from my Old one NoW I remember what it was My Dash

Is the black wire coming out of the 2 position plug the same one that is connected to gnd. ?? If it is that is your error. Refer to my previous post.

efi-diy,

Yes; it is the same wire. I just assumed the way the connector was made and the short length indicated a ground. Perhaps the harness manufacturer was thinking is should go to the BAT terminal. It would fit there.

This was the diagnosis I got from another forum as well. Where would you suggest running this wire? Should I go directly to the battery? Ignition switch? Starter?

Thanks a bunch.

Jerry

Ok; I connected that black wire to the BAT terminal and voila, I am charging. I'd still like your recommendations on the 'better' place to run this wire. Thanks for all your help. I'm goin' cruisin.

Jerry

Dear Jerry;

The black wire from the (2 prong) socket goes to the igniton switch to 'feed the alternator' when the switch is in the 'on' position only.

The blue wire is for the light (if used).

The large (#10 red) wire loops through the ammeter.

The black ground wire goes to the firewall where the old regulator was mounted.

Goodl luck.