Suggestions for electrical hook up for Transmission Cooler

[Carolina_Mountain_Mustangs]

This week I am installing a Hayden fan cooled automatic transmission cooler to my 73 vert.

I am trying to make the car more trust worthy for longer trips for several hundred miles. With my 351 being bored .050" over, cam and flat top pistons I need to take all the heat out of the radiator I can.

So I made up brackets and I am putting the cooler in front of the radiator support to the R.H. side as far as I can go. I did not want it right in front of radiator would still just add heat back to it. Will get some pics today when it is mounted back on. I painted the brackets yesterday and will go back on today.

My questions is what is a good place to pick up a 12V supply to run the fan on the cooler? It says it draws about 6 amps. I am adding a toggle switch so I can turn it off if not needed in winter. I also picked up a fuse holder and figure on a 10 amp fuse for the connection. Was just going to leave all the wiring and switch under the hood area and not run inside the car. I always unhook battery when I stop or park the car.

I am close to the solenoid and voltage regulator so I hope something there I can tap into.

Will be forming up some new metal lines to connect to the transmission and get up close to the cooler then use rubber lines for the final connection.

Hope to drive it down to the MOM on 29th. for the all Ford show in the morning and then stay for the Hornets Nest club meeting and tour of the Carpenter museum that afternoon and then back home. About 230 mile round trip. Will drink the gas but want to drive it some to shake down any more issues left from the PO doing things wrong.

Looks like I will be pulling the pan off the transmission soon and replace the seal on the shifter. It is a C-4.

 

[Bentworker]

6 amps is enough that you might want to use an aux relay, just to make life easier on the ignition switch and harness. I'd hide the aux relay wherever is handy up front, run non switched power straight from the battery to the aux relay contact (preferably fused), then to the fan. Then I'd use whatever small gauge wire is handy to go from an ignition on source to the coil of the relay. If you really don't want to run it seasonally just unplug the relay (get a relay that has a base that it unplugs from) and forget about the toggle switch. Sometimes simpler is better. You should be able to hide most of this, and do it without penetrating the firewall at all - unless you really want an off toggle.

 

[Jeff73Mach1]

I suggest wiring it with a relay and a line to the battery for power. To power the relay, just pick up any ignition on power source preferably at the fuse block to trigger it and wire your switch in there. If you forget to turn it off, it will still go off when you cut off the ignition.

 

[Don C]

+1 on using a relay. Does it have a thermostatic switch, or just controlled by the toggle switch?

I would connect to the battery side of the solenoid for power to it. Because it's a '73 it probably has the throttle position solenoid and the power lead to it would be a good source for keyed voltage to operate the relay, unless you want to have the toggle switch inside, and were planning to run a wire from the inside. You could always just pull the fuse during the winter, or when you don't want the fan to run, if you would rather not run a wire from the inside.

 

[Carolina_Mountain_Mustangs]

I did end up hooking to the + side of the solenoid and put an inline mini fuse and put the toggle switch below the fan. I put in a 5 amp fuse and it pops it so went to 10 and worked. I drove to gathering at our local outlet mall last evening and when I got back hole the return hose on the cooler is cool so it does a great job of cooling for sure.

One thing I have noticed when driving at night. When I turn the headlights on the temp gauge rises. Does that affect the voltage going to the gauges and cause them to vary?

There was a 72 Sprotsroof at the meet last night first time I had seen it. 50,000 mile second owner car H code. They had lots of questions. He was having heating problems and he was told to remove the baffle under the thermostat and it made it worse, lol. Do not know why people keep doing that. Steered him to parts house that has the correct thermostat so he can get it back correct.

So now if I can get the AC to going will have most of the bugs out. Will also need to order seal for the shift lever on the C-4 it is leaking for sure.

Left camera in garage will post some pics later.

Got to find a show for today will go to local facbook page that lists them all.

Thanks for all the insight on the wiring. If it pops fuse I will install the relay.

 

[Don C]

There are 2 commonalities between the headlights and gauges, main power feed and ground. If it were the main power feed causing this the gauge would likely go down, not up. So, that leaves the ground that is common between the dash lights and high beams on light and the instrument voltage regulator in the circuit board. To test this, turn the dash lights up and down and switch between high and low beams. If this also changes the temperature gauge reading you'll know that it is a grounding issue, either the ground wire connection or the contacts in the circuit board connector. The additional loading the on ground circuit, by the lights, also reduces the ground for the instrument voltage regulator, causing it to raise the voltage to the gauges.

 

[Jeff73Mach1]

The relay protects your wiring from carrying too much current that is to say, more than it is designed for. If you have blown a fuse, you are already at that point.

 

[Carolina_Mountain_Mustangs]

I took the car on over 100 mile journey yesterday. The cooler had no issue. The first fuse I put in was 5 amp and the fan I believe pulls over 6 so I expected it to pop. It has 14 ga. wire and 10 amp fuse now.

Checked the temp of the hose coming out of the cooler and the oil is cooled way down not even warm to touch.

Bad thing was it poured the rain from noon until I got home about 6:00. Was parked most of the time show was a bust and swap meet with all the rain.

On way home had to hide behind a building for a while was blowing trees down and rain so hard no way to drive.

First time the car has really been wet in 27 years.

On the cooler I think they forgot to include the instructions because there were none. Just some info on the box about size and a sheet in the box that was for just a cooler with no fan.