Cooling system related, dual electric cooling fan system info, in case anyone is interested in doing that kind of conversion:
When we acquired our 73 Mach 1 I was aware the prior owner had replaced the original 302 and swapped in a 351W (not C). He also had the 351 built to put out a respectable 360 HP. Apparently, in a bid to help keep the new engine running cool, he replaced the original radiator with a wider 3 row brass radiator meant to be used with the larger 351 or 429 engine (429 was optional in 1971, but not in 72 or 73 for street use). That was fine, but for some reason the original fan blade and radiator shroud were used - where the shroud was definitely too small to provide the kind of airflow the larger radiator needed. At prolonged idle or slow driving the engine coolant temp would climb up to 240 degrees. The prior owner was not aware of that as the original instrument panel had ***** lights, and the temp light never illuminated (at least for me it never did). But, one of the upgrades I did was replacing that original ***** light laden panel and installed a Dakota VHX analog gauge instrument panel. With that I could see the temp climb up to 240 degrees, but once I was running at more than 25 MPH the temp came back down to the 190 degree level.
I know I could have simply gotten a larger fan, with the proper fan clutch, and a wider fan shroud made for the wider radiator, and everything would have been fine. But, I had long wanted to do an electric cooling fan conversion, and here was a perfect excuse to do a conversion on a car I did not mind modifying (I would not have done this to our 1969 Shelby GT500. That is being kept pure stock). I got most of my parts from PerformanceCooling.com, where they offered a radiator.shroud, dual electric fan kit, plus the thermal switch and relay for the fan control. The kit installed fine, and worked well. But, I decided I wanted my fans to come on at 195 degrees, not the thermal switch's preset 180 degrees, as the engine cooling thermostat was a 195 degree unit - which meant the fans would be on all the time whether they were needed or not. I did not want them to be running if they were not needed. Here is the YouTube showing how I did the conversion to the dual electric cooling fan system:
https://youtu.be/T5DrC2zrpIA (This is on our 73 Mustang Convertible, following the successful conversion on the 73 Mach 1).
I found a variable temperature thermostat and installed it, and set it to a 200 degree level before it signaled the fan control relay to send electrical current to the fans. It worked (and works) perfectly. But, I still felt the need to do some more enhancement, just because the geek in me can make me do crazy stuff. I decided to acquire an LED light panel that I could set up to illuminate its amber LEDs any time the cooling fans had power sent to them. I got a dual LED light array (Amber and Red) and ran a parallel wire from the triggered side of the fan relay to the Amber LED light wire for the LED array. The LED array is adhered under the driver rear side of the hood. so only the driver can see the LED lights come on when the relay has been signaled to send power to the fans.
So, why the dual colors for the LED light array (amber and red)? Well, for a future upgrade, of course. I thought it would be really nice to have the amber LEDs come on when the fans were getting current, but it would be really nice if I could turn on the Red LEDs if the cooling temp exceeded 220 degrees for some reason. I have not yet set up the dual triggering for the thermocouple for the variable temp switch. My initial thought was I would have to install two variable temp switches. But, recently I came across a dual level adjustable thermal control switch switch that can be run from a single thermocouple. So, I can set one of the thresholds to 195 degrees, and the other to 220 degrees while keeping the existing thermocouple in place and not having to add a 2nd thermocouple. I have yet to do that upgrade, as I just recently received the new dual level control unit. Once we get a warm day I will begin to work on that enhancement. Meanwhile, this is how I set up the "Fan On" amber LED notificstion sytem:
https://youtu.be/ErDOMJ1hOnA
Meanwhile, in case anyone is interested in the dual electric fan upgrade, and/or the Fan Relay Power Monitoring LED system, I have some YouTube links below showing how I did all that. The descriptions provide the parts listing. I got all the parts from Amazon vendors. This was a really fin project, and the electric cooling fans work perfectly, At least now they do... Confession time, below...
I first did the electric fan upgrade to our 73 Mach 1 in order to resolve a temperature rise at extended idle or prolonged slow speed driving. That worked out so well well that I decided to do the same enhancement on out 1973 Mustang Convertible that had absolutely no such cooling problems with its stock 302 and original cooling system. Clearly I have not learned the sage advice of, "If it ain't broken don't be fixing it!" heh heh
The 72 vert upgrade went as smoothly as the Mach 1 dual electric fan upgrade, and everything seemed to be working well. Then, in Summer 2013, I decided to bring all four of our pony cars to a local car show, about 25 miles away from our home. Lynda and I would be driving the 1969 GT500, a friend would be driving the 2020 GT500, and our soon-to-be-daughter-in-law and son would be driving the two 1973 Mustangs. Heather (future DIL) picked the vert because it is so cute, heh heh. Well, when we got to the car show location there was a long line of registrants. I got a call from Heather advising the engine temperature was climbing. I told her to not worry unless it hit 240 degrees. Well, not long after she called and said it was over 240 degrees and lots of steam was coming out from under the hood. WTF?!? She had, by then, pulled to the side of the road so she would be blocking traffic. We let it sit there, in a safe area, for a few hours. Then after it had time to cool off, I walked out to its location (just at the edge of the park grounds) and popped the hood and filled the radiator. I started the engine, and everything looked fine. I changed the thermostat dial to trigger the fanr elayh to its minimum temp, I think 70 degrees, and nothing happened. I had no tools or test light, but by chance I did have another fan relay in the center console, just because. I swapped in the new relay and nothing happened. So I figured the capillary tube thermostat must have failed, so I jury rigged the fans to run all the time, whether needed or not, until I could dig into the system and fix the problem.
We got the vert out to the car show grounds, then back home with no further incident. Then I began to diagnose the real problem. Lynda video taped the diagnosis and repair, where the video is posted on YouTube at:
https://youtu.be/Du8vPpsrINA Spoiler alert... the problem was an unexpected bad ground connection despite my having tried to ensure all connections were good when I did that electric fan upgrade months earlier.
Sometimes I think I have a little too much fun with these cars... heh heh
