The Stovebolt Site Forums The Shop Area The Electrical Bay 6 volt question

I have a '51 chevy 3100 that I am trying to get started. The engine is not original and looks to be at least 1957 235. The question:

Is it possible to visually tell if the system is 6 volt or 12 volt? If the engine was changed to a 1958 235 would they HAVE to switch the system to 12 volt?

Hey Purney, no, you wouldn't have to switch it to 12v but most engine upgrades include the changeout to 12v. Just look at the battery, if it has 3 cells (3 water caps) it's a 6v if it has 6 cells, it's a 12v.

Purney,

The first check would be the most obvious...the battery. More clues might be the presence of a ballast resistor on the firewall, although this isn't 100%. The coil might have its operating voltage stamped on it and if you are industrious, the headlamp or a taillight would have a telltale number on it.

The '58 was a 12 volt system and its starter would probably not work with a 6 volt system...the '51 starter could work with a 12 volt system. The battery will be the place to start...look for more than three caps on the cells or put a voltmeter on it.

EDIT. To answer your original question, no, they would not have to change to 12 volts.

Stuart

Thanks for the quick response. The battery that was in it had only the 3 caps, so then It should be a 6 volt. There is a black box on the firewall (driver side) It says Delco Remy but nothing about 6 volt.

In searching the forums I did notice that I bought the wrong Battery cables, I got the 4 guage type. I will return and get the 0/0 gauge. When I hit the starter on the floor I heard a spark or a faint click and the gas gauge needle (the only thing that moved on the dash when I turned the key before hitting the starter on the floor) went dead, now it doesnt move when I turn the key. Is there a fuse or something that I blew? I also put new plugs in and wires so I know this girl will run If I can get the starter to turn! It did turn slowly one time early but now nothing!!

Purney,

The black box on the firewall would be the voltage regulator. I don't think there is any fuse for the fuel gauge. When you install the new cables, make sure the ground strap has a clean place to bond to. Batteries can be deceiving..make sure it has clean posts and a full charge. If it is questionable, have it load tested or buy a new one. With the fat cables you are going to install ( great sleuthing) and a charged battery, the truck should turn over briskly. Good luck and a belated welcome to the Stovebolt.

Stuart

Great stuff Stuart. I am working with a new battery so that should not be the problem. If the new cables and clean hook ups dont work, what is my next step? to check if its the starter or did I blow something?????

Thanks for the welcome and I appreciate the help, you guys a great.

Purney,

There aren't too many things to blow on these old rigs. As you point out, the next suspect in the game would be the starter. It can be gummed up and can actually drag the armature on the field if the bushings have gone south. I'm not sure I remember this properly, but with a fully charged battery and good cables and clean connections, you can turn the headlights on and try to start the truck.

If the headlights almost dim to nothing and the rig cranks slowly, it's a battery problem...if the headlights only dim slightly and the rig cranks slowly, it's a starter problem. This is a shadetree test, and I might have it bass-ackwards, who knows.

Double verify the cables and connections and make sure the battery is up to snuff. A inexpensive hydrometer will give you a great indication of the state of charge on the battery, plus you can impress your friends and baste turkeys on Thanksgiving.

Stuart

Stuart,i am inpressed, mate with out giving you a fat head one reason i joined the bolters was after monitoring the forums i found that members just want to help,Purney mate if these guy's cant help they will at least say so,suggest someone who can or try to lighten your load with a bit of friendly banter,if i didn't know better i would swear the where all Aussies (tongue in cheek),welcome aboard,these guy's work on the princible if you cant do someone a good turn don't do someone a bad one.just my opinion and with respect to those that want to repeat yesterday's mitakes(not that they made as many as we do today) 6volt system :blat: it's a fine line you tread when you only start with 6 of the best and 3 go missing more the maryier i say.

Thanks Stuart. I will try again tonight with the right cables. If I cant get it to turn then It must be the starter. The wiring inside the bay is original and in pretty bad shape. Electrical is not my thing so look for me often!!! Thanks again for your kind help everyone.

got the cables, buffed the frame to bare metal where the ground strap goes, did the same on the brass ground strap that goes from starter to frame. Battery tested full charge Got ready to put the positive cable on and realized that I bought one that was a ground not a battery cable! GRRRRRR! i will let you know what happens tomorrow when I get the right cable on............

as a note. 12volt regulators, generators, coils and so on from the early years are stamped 12V or 12 Volt. The six volt stuff is not usually marked.

Update on my saga. Hooked everything up, got power to the gauges, but starter did not turnover. took the switch off the starter and discovered much wear. I touched the battery cable to the metal plate on the starter and got a big spark and the starter turned over! Engine didnt catch but I also didnt hold it there for long. Ordered the switch part from NAPA will get it tuesday. Question for you all. Should I be concerned about the spark? (short?) If the starter just turns but doesnt catch what is my next move? Thanks guys!

DUH!!! It wont engage until I push the starter button on floor wich will engage pinon to flywheel!!! Anwered my own question, you guys smarts are rubbing off just being on here!!!