I am converting my 1947 Ford to 12 volt negative ground. I have the factory fresh air heating system in it. I am trying to find a replacement motor. I can find motors but no one knows the dimensions for me to verify it will fit. Has anyone done this before and have a source or motor number I can look for? I have attached a picture of the blower housing and motor on my firewall for reference. Thanks in advance for the replies.
I took my motor to the parts store and looked in the Murray components book. They have pictures and measurements in the back of the book that should help you match it up. Mine is an old Sears Allstate.
A resistor will help lower the voltage. When I converted a 53 Chev to 12 volts one of the things I didn’t change was the heater motor. Ran great especially the defrost feature; never failed or burned out in 3 years. I would take your motor out a and then search if you want a change. Mic the shaft diameter so can get one the same size for the fan. Then start looking for anything newer than 55-56. It’s ez to make a flat donut and mount it. Good luck.
Have a look on the " DCM Bus site " and the " NAPA site " both show blower motors c/w with dimensions.
I think you'd be hard pressed to find a computer fan that moves anywhere close to the same amount of air that a typical blower setup in a car does. Plus a computer fan doesn't work nearly as well as a squirrel cage blower when it come to moving air through ductwork.
i tried the computer fan, didn't move much air. there has been a napa # posted here before, search "12 v fan hamb" at google
If the 6v is in good condition a Napa voltage reducer will work, if you want more air flow then a later multi speed 12v is needed. I used the voltage dropper in my Crosley with a "switched jumper" to get more speed/flow when needed.
Here is a scan of a good Rodders Digest article and several pages of PNs and dimentions of blower motors from NAPA
I have some pages or a illustrated guide here somewhere......I was doing the same thing for a regular '47 fan, couldn't find anything and was going to look into getting it rewound. If your going to use a reducer, make sure it can handle the amps and you put it in the engine bay (they get hot)
If you do use a resistor, the best place to mount it is right at the inlet or outlet of the blower. The higher speed you run the blower the hotter the resistor gets, but you also get an increase in airflow to remove that heat. Bonus: The heat generated by the resistor is put into your heater ducting. For a lot of year GM and I suppose others did just that, with the speed selection resistors hanging in the ductwork. Go to the salvage yard and get one of them, you can wire a couple of the coils in series and use it to run your 6 volt blower motor.
Yes, the best place to mount the resistor is in the air plenum where there is plenty of air flow to cool the resistor. For my money, I think I'd find a 12 volt motor that fits, I've never had any trouble matching one up. Note: the slower you run the fan motor the hotter the resistor will be. On high speed, the resistor is out of the circuit and the fan motor gets a full 12 volts.
I used this in my '54 when I went 12 volts the shaft and the bolt spacing was the same as the old six volt it replaced. https://www.grainger.com/product/DA...CH7&op=search&Ntt=3LCH7&N=0&GlobalSearch=true
V8 Bob has a part no. for a NAPA replacement 12v motor that works on '40 heaters. Maybe he'll jump in. He told me the number , but I forget ...... big surprise.
Have you tried running your motor with the 12 volts heater motor in my car is original 6volt been working fine for 40 plus years [Q
When I converted my '46 to 12 volts I purchased a motor from Dennis Carpenter (R.I.P.). It fit like it was made for it. Part number B6A-18527-B. I believe it is for a '56 Ford. The sticker on the motor reads, FASCO, 12v., 2807-406-074
Joel, I also forgot, except I kept the box! The 12V replacement motor is NAPA/Balkamp 655 1022. The shaft may have to be shortened but otherwise matches the dimensions of the '40s Ford motor, is two-wire but reversible.
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