OK, the first roadside repair on my new ride

[Mark Haymond]

http://www.smugmug.com/gallery/22193746_fWznm6#!i=1772379467&k=h6vxcK9

I have been doing daily trips around town for a couple of weeks in my 47 Plymouth. I have a Mopar 318 with a 904 Torqueflight automatic in it, my first V8 conversion project. I thought I was doing well until it overheated in the drive through at Starbucks. Grumble. The Hayden electric fan controller did not turn on the radiator fan, resulting in overheat, overpressure (seven pound radiator cap) and it ruptured the heater core inside the car.

I felt lucky to a certain extent. I had shirt sleeve weather to work in, I was 100 yards from a gas station, and a quarter mile from an electronic supply business. I jumpered around the fancy shmancy controller with a short length of wire to give power to my electric fan. And I re plumbed my longest heater hose in a short loop back to the engine to take the leaking heater core out of the coolent circuit. I was able to get back home without AAA service.

Of course if my old flat head was still in the car with the four blade metal fan I would not have had a fan failure. The upgrade seems to come with a reliability price. Sigh.

Edited March 31, 2012 by Mark Haymond

[Don Coatney]

Mark;

On the Hayden controller there is one wire (yellow if I recall) used to start the fan everytime the air conditioner is turned on. With no air conditioner this wire is not used. I connected a toggle switch to this wire (as seen to the left of my ignition key) so I can manually turn on my fan in such an emergency. I also carry a spare plug in relay in the glove box.

[Mark Haymond]

With my first hookup my controller would run the fan whenever it had battery power and the sensor felt the right amount of radiator heat. After I turned off the car the fan would cycle on and off repeatedly for a long time and I found that annoying. So I ran a small yellow controller enable wire to my ignition switch. Then the fan would operate only when the radiator was hot, it had battery power, and the ignition was on. Until I get my old heater core repaired, I am using a simple twelve volt, thirty amp plastic relay to operate the fan. I have the coil of the relay connected to the heater switch on my dash, since I temporarily don't have a heater. And yup, I am now carrying a spare relay in my tool bag.

[Frank Elder]

I wouldn't call the 318 an upgrade...only an engine swap:p