Regulator issue if at 18 volts?

-
T

TheBigE

70 Duster - Slant 6
Joined
Dec 4, 2008
Messages
89
Reaction score
1
Location
London, Ontario, Canada
Hi folks.

My factory bone stock 70 Duster slant 6 car is showing just over 18 volts on the battery when idling and the headlights get super bright!!!! I'm assumming that it should never go over maybe 14 volts and that my regulator is bad???

Thanks for any help.

The big E
 
Mine was doing the same. I rewired it and put a 71 and newer regulator in and its all good. I'll see if I can dig up the thread for you that the guys helped me out with mine in.
 
My 70 Swinger had that issue last summer. I was driving it and evrything got real bright. The volt guage was pegged on the charge side. After awhile it did just the opposite. Went to the discharge side and everything got dim. The car still ran but I shut it down so as not to have any wiring issues. Got it home and opened the hood to find that cider like sticky crud leaking out from the bottom of the regulator down the firewall. I put a new Advance Auto Parts regulator on the car and the problem was gone right away. Good Luck!!
Chas.
 
thanks for the interesting info men.

I will be changing over to electronic ignition at some point...but for now I'll try another old style regulator and see what happens! This one on there may well be from 1970!! Should the voltage be about 14 or so???

Big E
 
Could be the regulator or it could be a bad ground connection between the regulator and the body of the car.

BTW, if you get a new replacement regulator it will most likely have electronic guts. Its actually cheaper to make them that way than with the mechanical guts.
 
Always best to check the simpler(and cheaper) things first. Especially since I'm after electronic ignition soon. I'll confirm that my ground is good at the firewall for my regulator and make sure that it is actually the regulator. I know that my only ground at this point coming off the battery is to the engine block!!! There is another black wire coming from the battery to the inner fender for body grounding but it is broken completely off!!!! I will fix this first. SHould there be a ground strap on a slant 6 from the engine to the firewall for more chassis grounding in 1970??? I see that the starter is only grounded through the engine black, an amazingly simple engine and electrical setup.

Thanks.

Ernie
 
My Duster used to do the same thing on occasion. The regulator was losing ground. I cleaned all the rust/paint out from under the mounts, screwed it down and sprayed clear lacquer over the mounts. Problem solved.
 
check your battery, as it might be boiling over. Add distilled water as needed. Check that your field wire from the alternator is ok and hooked up too(green wire) .I had to scrape off paint from the firewall to get a good ground after this happened to me.My regulator failed.
 
Bought a new regulator from an outfit called Battery Supply here in London. They had one in stock for only $8!!!!! COuldn't go wrong here. Put it in and got to an instant 14.4 Volts. Very nice. I will certainly check my battery though...no telling how long it's been like that!!!!

The Big E
 
Thats what worked for my car. Since the voltage regulator replacement I have had no issues. By the way, I do have a ground strap on my motor. It goes from a bolt on the back of the head to one of the bolts on the blower motor. One thing that has made a major difference was new battery cables and ends. I used to have that 'surge' where the lights got dimmer at a stop light and when I stepped on the gas they got brighter. I cleaned the ground area on the motor mount bracket where the ground cable goes as well as the area that the small ground wire that runs from the battery to the core support right near the battery goes, cleaned all other connection areas and no more surge issues either. Just a little tip that may help. Good luck!!
Chas.
 
Every dog has their day I guess...and I had mine when the voltage came down nicely for me.

Interesting engine ground strap location. So is that blower motor bolt one that goes through to the engine side of the firewall? That would make for a solid ground I guess to the dashboard area.

SO that broken wire I have coming off of the negative battery cable then grounds out at the rad support?? Is it short then like 6-8 inches only? I thought that it grounds with others maybe next to the battery on the inner fender. I think there are 2 grounding wires bolting in there.

I'll have to check mine for light brightness on idling to driving once I get it on the road. I know that the headlights went super bright from engine off to engine on with my bad regulator!!!!!

The Big E
 
Big E, that ground wire is pretty short. Look just in front of the battery closer to the radiator. You should see a 3/8 bolt with something already grounded to it (turn signal ground). That is where this little ground wire goes. On the ground strap it is bolted to the back of the head and runs to one of the four bolts on the ring around the blower motor. The one closest to the motor. Check that area where the big battery cable on the negative side grounds to. It should be on the front side of the left motor mount. If this area is dirty it will play games with you on starting from time to time.
Chas.
 
You must log in or register to reply here.
-

Back
Top