Hey guy's, I picked up a 1946 Ford and 2 speed 6 volt heater. My 46 has a 12 volt system, have any of you guy's used a 12 to 6 volta Drop successfully with a heater? I thought if I fed it with a fused dedicated 20 amp 12 volt circuit with a 6 volt runtz type volta drop would be OK. However I was just told I needed to use the new digital type volta drop type unit that comes with a small box to ease the load to the heater. What do you guy's think? Should I include a relay in this system? If so, should it be a 6 volt relay installed between the switch and heater?
Just what voltage reducer are you thinking of using? Most of these are designed for relatively small loads, and even some of the larger ones won't like the current inrush from a motor. If it were me, I'd look for a 12V replacement motor rather than using the 6V one. Most of those fan motors are 'universal' type, there's a large selection of replacements with different case/shaft sizes available.
Napa sells the big porcelain reducer made especially for heater fans. Very specific and not for use on gauges.
If you looking in Napa book you can probably find a 12 volt motor that has the same outside dimensions it's just swap the motor over Sent from my SM-G550T using The H.A.M.B. mobile app
12 volt motor is the answer . When you drop voltage by 1/2 you up the Amp load x2 . Voltage reducer will be hot enough to ignite flammables after 1 hour of operation . Just something to think about . I changed 48 F1 to later 12 motor very easily . Motors usually have a standard frame size to work with . Just my 2 cents Sent from my iPhone using The H.A.M.B. mobile app
I have used larger computer 12V cooling fans on old 6V heaters and works well and really cheap at surplus shops...
As others have said, don't even attempt to use a reducer, swap out the motor. I nearly set my truck on fire trying to run a 6V blower motor through a voltage reducer, the reducer was attached to the bottom lip of the dash and got hot enough to blister the paint on the dash.
I used an ordinary ignition coil ballast resistor in the supply side. Worked fine. To check if resistor is near correct, measure voltage at motor connection while on high speed. Anything under 8volts should be fine. Garpo
I had trouble with my six volt motor in my auto therm heater. I was able to find a 12 volt motor on the NAPA web site. All I had to do was cut some of the length off of the fan shaft to make it work.