510 charging problem

[Joecey54]

So it all started one day when I was driving up to Tahoe for a nice drive. As I was driving i noticed my charge light was coming on and off. After further inspection it seemed to come on at lower RPMs so I turned around and drove home. When I got back I started to check the connections and if I moved the two prong connector that goes into the back of the alternator the light would go off and the alternator would charge. The problem was that I couldn't find a new connector so I crimped on some spade wire connectors just to stop the problem for now. Well that didnt solve it, so i figured it had to be the alternator. after replacing the alternator and the voltage regulator its still not working correctly. And to add to it if the regulator is plugged in the car will not turn off. but as soon as I discconect it it turns off. I am now very lost. could it be that I switched those two wires??? I dont want to start moving wires around in fear of blowing the whole thing up. Any ideas would be helpful!!!!

 

 

Thanks

Joe

[Joecey54]

Also if the voltage regulator is plugged in it puts out 15 volts if its not its just battery voltage.  not sure if this helps any.

 

Joe

[MikeRL411]

Did you put in an internally regulated alternator and leave the external regulator connected? That's what this sounds like. Subject has been beaten to death but keeps regenerating, must have Zombie bloodline.

[Joecey54]

How would I find that out?  It did not look internally regulated to me.

[datzenmike]

So it all started one day when I was driving up to Tahoe for a nice drive. As I was driving i noticed my charge light was coming on and off. After further inspection it seemed to come on at lower RPMs so I turned around and drove home. When I got back I started to check the connections and if I moved the two prong connector that goes into the back of the alternator the light would go off and the alternator would charge. The problem was that I couldn't find a new connector so I crimped on some spade wire connectors just to stop the problem for now. Well that didnt solve it, so i figured it had to be the alternator. after replacing the alternator and the voltage regulator its still not working correctly. And to add to it if the regulator is plugged in the car will not turn off. but as soon as I discconect it it turns off. I am now very lost. could it be that I switched those two wires??? I dont want to start moving wires around in fear of blowing the whole thing up. Any ideas would be helpful!!!!

 

 

Thanks

Joe

.

 

If your external voltage regulator is still on the strut tower behind the battery, and if it is still connected to the harness on your car, it's safe to assume that it hasn't been changed and has the stock external regulated alternator on it.

 

As you have replaced the alternator, it should have a sticker on the side. Alternators requiring an external voltage regulator (yours) will have LT1 marked on it somewhere. Alternators used after '77 with built in regulators are marked LR1.

 

 

The flickering light and the seemingly loose connection could also be worn out brushes. The two prong connector is part of the brush assy and wiggling it could make or break a worn out brush ... and easy cheap fix.

[banzai510(hainz)]

get a volt meter on the battery while running and monitor the voltage and put lights on. wipers and such.

write down the voltages and tell up.

 

By the time the light comes on its already to leate in most cases.

 

there are cheap cig light install diode volt monitors that work also.like below

 

I used to run this before it broke. I think they only worth 10$ but they work well.

http://www.equus.com/Product/3721/Battery-Monitor

[Joecey54]

I pulled the alternator out this morning and took a couple pictures.

 

 

 

 

 

I will put it back in and get those numbers.

 

thanks

[Joecey54]

After doing some research I found out that its a alternator for a 1978 620. After talking to the auto parts store they told me that it is internally regulated. So thats my problem.   After searching I am still not 100% sure how to wire that in.

 

Thanks

[datzenmike]

Their mistake so take it back for the correct one and it will go right in on the old wiring. Besides your alternator is 50 amp. The '78 truck is only 38 amp.