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My trucks finally gonna come out of storage for good! I have a 1953 Mercury M350, I believe years ago grandpa had converted it to 12V from 6. Sadly I can’t ask him anymore questions about this truck it’s all me now. Other than a voltage regulator that says 12V 30A, I cant find any other evidence. Solenoid looks old and stock like. Can’t see any added voltage reducer near the gauges and the generator looks like a crusty old generator. Regulator easily could have been a “farmer find in our pile of spares” not necessarily a proper replacement part. It has ran like this in the past and I’m kinda sure it’s been a 12v negative ground battery in place. Anything that’ll make this more obvious for me or am I best to do a conversion using an alternator and make sure all the proper parts are there?
Also, what engine do I have? 255? 239? (I think those were my flathead choices?) I’m not really a flathead guy, yet... It’s bored 60 over and used to run really good cold. Little hesitant and stuttery when hot. Gonna get it tuned and running smooth
Based on your description I would guess it has been converted to 12v. You might take out a headlight bulb and see if it's marked 6v or 12v. That would be a quick and easy thing to check.
I didn’t see a ballast resistor on the coil and I tried to look on it for markings showing internal ballast but no words or markings besides + and - . I haven’t pulled bulbs yet but I’d assume if they were 6v and it’s a 12v system being used they’d be burnt out since it’s been this way forever. So I guess I can check that easily. Under the dash in the gauge department, what would I see or what do I look for that’d convert 12 to 6 for the gauges?
You can crawl under the dash if you want, but I mentioned checking a head light sealed beam as they're right out front and you can remove one easy with just a few screws while sitting on a chair, instead of breaking your back and working upside-down. The miniature dash bulbs would likely need a cross reference chart to check the number. Sealed beams are typically clearly marked for voltage.
You'd have to look under the dash at the power supply to the gauges. If it's coming straight from the ignition switch, still 6v. Typical converters/regulators for gauges either drop the voltage to all of them, or individually at each gauge. In either event you'll see something besides the stock single wire that feeds the metal straps connecting the hot sides of the gauges.
