VR and Alternator

Ok read through some threads but not finding what I'm looking for. 69' A108 318. When I got the van the fusable links in the VR were blown. Fixed it with a new VR and it was fine for weeks with a solid 14vlt draw reading. Blew one of the fusable lines in the VR again. Fixed it. Blew it again. Is my alternator putting out too much? They are cheap thinking of replacing it anyways but want to find out what's the problem. It seems to happen randomly.

Any help would be awesome.

First look at this primer I wrote.
https://vintage-vans.forumotion.com/t35895-how-to-diagnose-and-repair-electrical-problems

As outlined there, check the charging circuit for bad connections, cooked, worn or missing insulation and clean battery and ground connections.

Next, try to replicate the conditions that cause the link to burn. Start the engine and turn on and off different switches. If nothing causes it separately, turn on everything (lights, radio, fan) to load the system.

The charging system is supposed to handle supplying any and all electrical loads and keep the battery charged. It is the old style, which means it only turns on and off (points) instead of ramping up and down as loads are added and removed (electronic). If you can narrow it down to one circuit that is causing the link to burn, that is the one requiring too much current (amps). Since the van was designed, built and operated for many years without this problem, you can see that this circuit has an issue that is causing this problem. It is usually a poor connection causing increased resistance. It's usually either at a connector, contact (inside a switch or at the base of a bulb, or the brushes of the motor) or the ground contact. It can also be worn wiring shorting or not carrying the whole load anymore (corroded or broken strands).

You can get a resetting circuit breaker to bypass the link. These are installed in newer cars and also available from parts stores. Get one that is rated the same as the link (always 12V, usually 15, 20, or 30 amps like a fuse). Use thick jumper wires to connect this to the ends of the burnt link so you can keep testing without constantly replacing the link. Once you have found and fixed the problem, make sure to remove the circuit breaker and replace the link. If you leave the circuit breaker, it can cause a fire because it keeps resetting and supplying power to the circuit.

I would replace the mechanical VR with a solid state one (search these forums for the link to buy cheaply). and like Rd said, go through your wiring and see where the problem is.


I had what seemed like an overcharging issue myself, turned out there were some loose connections, hard sections of wire and other mischief, including the main #10 feed to the fuse box actually twisted to a piece of #16 for the last four inches of wire or so.

I made some repairs, changed out the VR and its working fine.

here is the electronic voltage regulator slowflapper spoke of.
http://www.ebay.com/itm/Mopar-Voltage-Regulator-Electronic-Solid-State-Correct-Restoration-Look-/121248291178?pt=Vintage_Car_Truck_Parts_Accessories&hash=item1c3af6196a&vxp=mtr

Thanks Dix for the link and everyone else for the tips.
Ordered that up and will check my wiring. I bet I got a weird wire or connection somewhere.
Do I need to change anything when I switch to Solid State?

no you do not BUT the ground is very important, if it does not tighten up to the fire wall for a lack of a better word then use a larger screw. and like rod stated look at all the connections and grounds, if they are rusty or wires are melted of stiff review those areas, what alt, are you running ?? more info can help us to help you,

Got the solid state VR. Went checked all connections on the alternator and found this fancy "patch" I don't think the wires were even touching. I replaced it with a fusable wire link, for just in case. I'm not sure what would happen to the solid state VR if I run into another issue like before. Hopefully this fixes the VR blues.

Here is a pic of the awesome patch job.

there is a red female plug in that photo that looks like orange wire to red wire with tape on it , you should follow that also,

dix wrote:here is the electronic voltage regulator slowflapper spoke of.
http://www.ebay.com/itm/Mopar-Voltage-Regulator-Electronic-Solid-State-Correct-Restoration-Look-/121248291178?pt=Vintage_Car_Truck_Parts_Accessories&hash=item1c3af6196a&vxp=mtr

yep, that's the one but the guy charges a bit high on ebay. I found manufacturer of the VR, called them and got a distributor number. I got them for $8 each with $10 S/H so you get two for the ebay price.

snip from a previous thread:
It's made/distributed by a company in Alabama called "Regitar", the part number is "C524", http://www.regitar.com

You probably wont find these at your local parts house, Advance, O'Reilly, and AutoZone didn't have them close to me. They don't sell to the public but they gave me the number of a dealer that carries the part.

"J&N"
Contact number: 1-800-366-7100

J&N carries a lot of old electrical components from what they told me, starters, alternators etc.

Replaced shitty patch job with fusable link. Installed solid state VR. Pulling 14.6v steady. So far so good.