Generator Light staying on

[Slimjim652]

First, it is a Fairlane 500 with a 312 and the generator was changed to an alternator from Mac's.

http://macsautoparts.com/1949-59-ford-mercury-alternator-installation-kit-12-volt-for-y-block-engines-b4a-10346-kt/camid/F50/cp/JS0R3CHL1111020/

The regulator on the car was removed and is wired directly to the alternator due to it having a built in regulator.  I attached  a photo of the back of the alternator.  Where the battery wire is connected to the battery and the white/black wire is attached to the Lite post.  The red/black wire had been eliminated due to being advised the ground was not needed.  If so I could hook the ground wire back to it if possible.  It ran great for awhile before the light started coming on since the light came on the alternator had been replaced by Becker's due to them thinking that there may have been a faulty regulator inside.  Since installing the new alternator the light is still on and will not go off.  I am going to try to test it tomorrow to see what the output is but does anyone know what would cause the light to stay on or how to remedy the problem.  Thank you for your help.     

[Ford Blue blood]

Was the generator keeping the battery charged or did you pull it off due to not working?  Not knowing the grounding and it's condition in your particular car the easiest thing to start with is run a temporary ground wire to the negative post on the battery.  If no joy get the alternator tested, might be two in a row?

[Slimjim652]

When I acquired the vehicle, the generator and regulator were already removed from the car. There was an ac-delco alternator on the car. It was replaced last year due to improper alignment. I'll try hooking up a ground today and run it to autozone to have the output tested. Thanks for your input.

[57 Ford Kustom]

Guys, speaking of the Gen light, I haven't hooked mine back up since the new wiring was put in, where do I hook it up to? Is it the alternator wire running to my fuse panel? Thanks, Tim

[Ford Blue blood]

That light is normally run in series from the fuse panel (switched 12V) through the light to the exciter terminal on the regulator or the terminal on the alternator.

[BWhitmore]

Could it be that the alternator has a bad diode which would allow voltage to feed back to the light constantly and the light stays on.  I know I once had a situation with a bad diode and the engine would not shut off. 

[57 Ford Kustom]

FBb, so I should take the alternator wire from the fuse panel, run it to the light and on the other wire run it to the alt? Tim

[Slimjim652]

I rechecked all the connections and verified the proper placement of the wires and I made a jumper from the ground post on the alternator to the negative post on the battery, with no success.  I did take the vehicle to auto zone where they ran a test on the battery and the alternator where they advised me that the alternator had no out put.  IS it possible that the alternator was DOA or do you think that the problem lies somewhere else.  I did also check the battery post on the alternator with a test light where it confirmed that the alternator was receiving power to it.  I was planing on taking it took a local alternator shop in town to determine if the alternator is functioning properly.  So at this point I'm totally lost.  Has anyone else used any of the Becker Auto conversions. 

Thanks,
Jim

[Ford Blue blood]

FBb, so I should take the alternator wire from the fuse panel, run it to the light and on the other wire run it to the alt? Tim

Yes.

I rechecked all the connections and verified the proper placement of the wires and I made a jumper from the ground post on the alternator to the negative post on the battery, with no success.  I did take the vehicle to auto zone where they ran a test on the battery and the alternator where they advised me that the alternator had no out put.  IS it possible that the alternator was DOA or do you think that the problem lies somewhere else.  I did also check the battery post on the alternator with a test light where it confirmed that the alternator was receiving power to it.  I was planing on taking it took a local alternator shop in town to determine if the alternator is functioning properly.  So at this point I'm totally lost.  Has anyone else used any of the Becker Auto conversions. 

Thanks,
Jim

Could be it was bad, doubt there was/is a problem with how you wired it given the two wire connection.  If the zone ran the test off the car or with your wiring completely disconnected then it is for sure dead.  The alternator shop should be able to tell you for sure and correct the problem.

[hiball3985]

It will be interesting to see what you find out. I considered buying this same set up to replace the GM 1 wire that I have now.. Becker sells them on Ebay for $140.
What type of Alternator is it? I didn't see where it stated.
Has anyone else used these?

[Slimjim652]

hiball3985

It is a Delco Remy alternator, but does not have any model number listed on it.  I'm having a hard time just getting the alternator tested alone due to how the plug is converted.  I am still waiting on an email or phone call back from Beckers.  It is definitely sold cheaper through Becker's directly then going through Mac's, wish I would have known that when I ordered mine. 

[hiball3985]

I'm just a shade tree mechanic but I've used a method for testing outputs for years if you want to give it a try. Start the car and turn the idle up to a higher RPM, say 600-800, then remove the positive cable from the battery. If the Alternator is putting out the engine will remain running. 

[Slimjim652]

While I guess I found the problem today.  Took the alternator to a local electric shop where the alternator tested fine.  He advised that the way the alternator is converted the idiot light is wired to tell the alternator to charge.  He advised that the problem lies in my idiot light wire getting a ground some where to cause the light to stay on therefore causing the alternator not to charge.  Guess the next step its to trace the wire back and try to find the problem.   

[57 Ford Kustom]

FBb, would the oilpressurelight be wired the same as the alternator light? Thanks, Tim

[hiball3985]

Interesting, this set up uses the GEN light wire to excite the alternator.