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4 volt battery

zimmy

Jedi Knight
Offline
well i bolted my solinoid to the car so it would be grounded..started her up for a few minutes....turned it off and went about my business for a while.....
i was still getting a glowing red light on revs.....
when i come back i notice i have no lights etc...nothin, so i check the battery and i get 4.3 volts!
so im guessing my alternator is shot and ive finally ran down my new battery!....everyone agree?
 
i would be checking that battery. did you measure the voltage while it was still hooked up?


mark
 
That's really low man. Your car should have not been running at that voltage. I would almost suspect the battery if it is displaying that type of voltage. Have both the battery and the alternator tested. Getting the alternator tested won't be as easy as the battery but there are places that can do it. Just not the ones that say AutoZone or Advance Auto on the door.
JC
 
Yup-yup. Light's gonna stay very red whether the alternator is working or not with the battery two-thirds hopeless. A specific gravity tester, a charger and a VOM are *kinda* indicated here as good things to have on hand.

Sounds as if you could 'short-cut' the process and just go get a new battery. It'd likely save all the argy-bargy of testing everything only to find it really IS the battery. Alternator output should be 13.5~14V at the battery when all is in good nick, running at 2500 RPM or so.
 
mornin' Jeff.

Prior knowledge? Is there a chance this battery is just heavily depleted, and the exciter wire has been disconnected for some time?
 
G'morning, sir. Jimmy posted in another thread that his alternator only had two wires going to it. I gave him the proper locations for the origin and terminus of the correct setup. Seems he was missing the exciter wire.
Jeff
 
ack. s'what I get for not spendin' time in th' spridget room.

I'll just slither back to th' Pub now. /ubbthreads/images/graemlins/wink.gif
 
it appears that the 2 brown wires go to the same place hence the reason there is only one....im gonna go get another battery today and then ill give you guys an update........
 
um... not quite.
 
please explain again Trevor...its seems the brown connections on the "lucas" alt are connected inside the alt....
i checked my battery today ..11.48 volts....not good..drains easily....also unhooked alt wires and the light on dash doesnt come on with key turned on....
signed:slighty cornfused
 
Jimmy, I just looked at my '74, and there is a flat white plug on the back of the alternator. Looking down at it, from the block out, are the small brown/yellow wire, the big brown wire, and then the small brown wire. The two brown wires are connected to the same terminal on the starter solenoid, but to different terminals on the alternator. If you are missing one of them, the alternator will not work.
Jeff
 
more info....my car wont start with the ignition switch, i have to jump it...my alt has 1 brown wire going to +battery teminal on the solinoid ...then it has a small brown/yellow wire which i assume goes to the red light as it works well!
there are no extra wires dangling anywhere in my car except for a slate one from the ignition switch...im really not sure if its the correct switch..it has 5 terminals...shouldnt i have 4?
need a pic?............z
 
What does the plug on the back of the alternator look like?
Also, what is the VIN of the car. There was a change after G-AN-5-138800. The later cars had 5 terminals on the ignition switch, earlier ones had four. If I know the serial number, I can make certain I'm looking at the correct wiring diagram.
Jeff
 
no plug big brown soldered to middle plug...little wire plugged into connection nearest motor.....GAN5 UE 145059 G
page 205 in the haynes...but im wondering also...
GOING TO TAKE PICS...........BRB
 
Jimmy, if you look closely, you'll see that there is what's left of a third wire on the alternator. There is a terminal there, but it no longer has a wire attached to it. Run a wire from this terminal to the same terminal on the solenoid that the big brown wire goes to. They should not be touching at the alternator. I'd try to find the correct plug if I could.
Jeff
 
Shouldn't be too tough to find a plug. If you can't find one, I've got one that isn't in too bad of shape, from when I converted my 76 to an AC Delco alternator.
JC
 
Sorry for not following up earlier. I was interrupted and was pulled away for the day. But it sounds like they have got you sorted out. DO you have a haynes manual with a wiring diagram? This probably won't be the last electrical issue you have. /ubbthreads/images/graemlins/wink.gif
 
im on Haynes p205.....what page do u suggest...p.207 seems closer strangly........
will try the extra wire tomorrow...thx guys
 
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