1938 V8 Help

G

G917t

Junior Member
Hello friends!

I am trying to get a 1938 1.5t Ford original 8v engine running. Unfortunately the guy who had it before me lost the generator.

To my knowledge it was converted to a 12v system with a step down to 6v for the distributor. The engine is a positive ground. The engine ran great until a few years ago when a short kept draining the battery and supposedly blew the old generator.

I went to MAC's and I was told the there are no 12v, positive ground generators. I also needed to know one, or two pulley. I am ready to get what I need for this and replace the wiring harness. Does this make sense to anyone or should I start over with an Alternator and positive ground? any guidance would be greatly appreciated.

Sorry for the not so clear engine picture. Its the best I can do until I get out to the truck again.

Thank you!

Tom
 

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I guess the lights are still 6 volts. I would go all the way to 12 volts. There are kits to fit the dist to 12 volt volts. The new wire from dist get a coil and resister for a 1968 chevy,then get a one wire alt one pulley.
 
With what little I know about your situation, I would suggest converting it back to 6 volts positive ground. That will make sourcing parts much easier, and I even have a generator you can have for shipping. I would also be suspect of the existing 12 volt conversion; in your post you state : "a short kept draining the battery and supposedly blew the old generator". That doesn't instill a lot of confidence in the job that was done. These old trucks have simple electrical systems, and since your are going to "replace the wiring harness" anyway I really believe you would be better off starting from ground zero. Spend your money on a 6 volt Optima battery rather than a one of a kind special generator. You'll be glad you did.

These vehicles did just fine on 6 volts when they were new and many out there are still that way. My own '51 with a bigger, modified engine is still 6 volts and I don't give it a second thought ever.

Oh yeah, and one final tip : There are a lot of better sources for parts than Mac's. Do some surfing around this site and you will find them easily.
 
Thank you for the replies. The lights and starter would be 12v, at least I have driven this truck many times with a 12v battery and everything worked. The current wiring is three generations of bubba'ing and I want to rip everything out. The truck won't be located at my place until I can get it running, so I am looking for a short term solution to get it home. If going 6v stock is that answer , it is the answer. I appreciate the offer on the generator. I will take it if 6v is still the way to go.
 
I take it your driving it home? Just put in a good charged battery and hot wire the coil. You can run 100's of miles
during the day like that.
 
If you are interested in the generator, please be aware that it is just one I have had sitting on the shelf for years. It is complete and looks good, but I don't know if it works or not. You should probably consider it just a core.

Also, I would be willing to bet that the starter is the original 6 volt unit that came with the truck. They work great on 12 volts and I'll bet there are literally tens of thousands out there (I know as I have two myself). Someone who would have wiring with "three generations of bubba'ing" probably wouldn't spring for a different starter.
 
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First, I'd just get the engine started, you don't need a generator or water pump belt to do that. There is no such thing as a 6 or 12 volt distributor. Just us any 6 or 12 v coil you have laying around. This is just an inexpensive way of learning how good the engine is. Do you know if it's an early or late 38, engine difference in engines./ AS for keeping it 6 volt pos ground. I think that's only for the purest. 12v Negative is more practical.. no need for a new starter I've been running my truck on 12 v for the past 10 years with the stock starter. Why spend allot of money, if you just want to get it running.
 
Didn't even think of that! Thank you. Will I need something in place of the generator to hold the pulleys so the water pump works if I will be driving 70 miles?
 
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Not sure why you are looking for a 12v positive ground generator, switch to negative ground. Nothing in the system really cares except the coil. Get a 12v coil either internal resistance of around 3 ohms or a 1.5 ohm coil with a 1.5 ohm ballast resistor and wire it for negative ground (the normal connections for a 12v coil).
 
Your problem is the original had the fan on the generator. Some folks changed the fields in the old generators to make them generate 12-volt like the 56 Ford generator then used the 12-volt voltage regulator from the 1956 on era. Now days there are the alternator conversions mounted in the old generator case set ups or the Powermaster alternators for flatheads that look like a generator. Later engines that had the crank shaft mounted fan or the belt drive 21A fan in 1942 thru 48 so they can use a regular alternator on them. Modern alternators don't have heavy duty enough bearings in the front to put a fan on there and hope for it to last any time at all. This is why a lot of folks mention going back to the old 6-volt fan mounted generator but it would be a kind of a hassle undoing all the 12-volt mods that may be in there. Many of the old generators were 3-brush set ups with a cut out only so they aren't anything to write home to mom about except all the trials & tribulations it's going to take to get there.

Those 12-volt converted generators don't grow on trees but it may be the easiest way to go. The alternator conversion of an old generator case is another possibility but those things are expensive and I don't know how reliable they are. I can see that your in kind of a pickle there.

This link shows a pic of an alternator converted for fan with the bracket installed. https://www.vintageautogarage.com/1933-1936-Ford-Mercury-Car-or-Truck-12-Volt-kit-p/f3336-k.htm

Like I mentioned, I don't know how well they will hold up but it might work for a while anyway. The illustrated kit is pricey but a person can buy the pulley and install it on a properly prepped alternator. It takes a bit to get the belts to align as a general rule. These set ups can be aggravating.
 
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Rotorwrench, thank you for the reply. I appreciate everyone's input. I am going to do the 12v alternator route and start from scratch with the electrical minus the starter. Thank you for posting the link it was very helpful.
 
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