I'm thinking about converting my 1949 buick roadmaster to 12 volts I'm sure its been done before just looking to see who and how its been done. The car comes with the big 1 inch belt that drives the water pump and generator, the belt doesn't seem to run all that tight. Can I just swap the generator pully onto an alternator and still be ok, or do I have to try to convert everything to thinner pullies and belts and try to run it tighter? I'm hoping to go with a one wire alternator and a drop volt to run the original dash and guages or is there something better I should be looking at? Oh great hotrot gods please show me the right direction I should go. Thanks Paul
to use the one wire alternator, buy a 5/8 wide pulley from speedway and have a machine shop open it up. i have converted some generators to 12v by changing the field windings. check with a rebuilder to see if you can do this.
You can just swap pulleys, and your'e good to go. Remove your wide pulley, measure the shaft or hole size, and head down to your local pick-your- part and start measuring up. You may have mis-matched pulley widths which may cause your tightness problem, or you may just have run out of adjustment on the generator bracket, which means you need the next size smaller belt.There are 3 terminal electronic voltage regulators available, part no. LM 7806, which will let you stick any voltage in up to 25 volts and you will get a regulated 6 volts out. Try an electronics supplier (I think one's called Radio Shack in the U.S. ).
Converted my 48 to 12 V last winter. I got a 12 volt alternator looking like a Lucas C40 Dynamo from http://www.racemettleltd.co.uk/. Not stock looking but a least look like something from the right era. They provided it with a split pulley and spacers. Very useful since I have changed the belt from a to thin belt (slipped at the fan) to the 1" belt. I just had to change the spacer. Everything else should be straight forward. I would skip the ammeter. Only gas gauge and clock that is electric. The blower seems to work on 12 volt so far. The starter might start to miss now and then. Starting to rotate before its correctly engaged to the flywheel. Another thing to think about is the accelerator pedal start system, if its still in use.
The starting circuit can remain as is.....Because it's "outside" of the charging circuits. If you just go to a 12 v delco generator,..(I assume the 6volt is a Delco), just swap the regulator for a 12 volt unit, swap out the pulley as mentioned, and away you go. Bulbs , flashers, fuel and temp gages, as well, of course. Happy Roddin'... 4TTRUK
You might want to check for fan blades on the pulley. The alternator has fan blades for cooling, and since the 49 Buick probably didn't have much in the way of accessories, the pulley may not have fan blades. Also when using a 7806 voltage regulator for gauges, make sure to mount the device on a clean grounded metal. These devices will warm up without some heat sinking.
The starter is grounded to the alternator, preventing accidental cranking when the engine is running. Thats why you need to connect it if you want the original functions. I run with a start button since I dont like this function.
BTW, no one makes a 12 volt starter solenoid for the str 8, so start buying spares now. Keep it tuned up so you don't have to do alot of cranking also.
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