Thanks Ray,
It helps to see other's cooling set up's. Good to see someone running without the temp controller set up. My son is 22 & drives the truck a lot - I don't have a lot of trust that he'll flip that switch on... Easily distracted...

You are killing me with this statement "In traffic, the engine runs at 180 degrees". I'm going to get there soon - can't wait.

Ben in Austin
1950 F1

 

I would recommend that the thermo wire be relocated to the top of the radiator, that is where the coolant is the hottest and would activate the fan speeds the earlier to give the best cooling effect. If all else fails, go with the 3300 cfm fan. After all, it is a minor investment to keep the trans cool while running the a/c in parade traffic.

 

deleted duplicate post.

 

This is the fan I used. Size 16 pull / Part# 2082 - The Fan Man
2500 cfm max @ 23 amps.
Look forward to getting you squared away!

Doug

 

If the engine is tuned correctly, not too lean and timing not retarted, then I still think this is just a simple matter of air flow and possibly just not enough fan. If you are going to make a enclosure for the fan it should not be 100 percent sealed, you need air flaps or openings to allow enough air to pass through when the truck is at highway speed. I have not needed one yet. A picture of your setup would be good.
This is the setup in my 37 Buick. 180 stat, fan comes on at 190, fan sensor is at the top radiator hose. Fan comes on and cools backdown to 180. fan never really comes on unless sitting in traffic. No fan enclosure but the fan covers most of the core.




This is the setup in my 47 cadillac. This is an LT1 with reverse cooling so the stat works a little different but it is a 180 stat and the fan comes on at 190. Settles at 185 and is there at all times unless in traffic, hits 190, fan comes on and cools back down. PCM is controlling fan action. Fan again covers most of the core. Both fans are Haydens. No idea what they are rated at but they move some serious air and are used by the OEMs. I buy them at swap meets for $10 to $20 each.



My only experience with header wrap was not a good one, got the pipes overheated and destroyed them. Peeled off the wrap and the pipes fell apart.

 

Ok Guys,
Here are some pics. Taken in the dark so not the best.
(2) of the Fan shroud area - looks to cover most of the radiator.

(1) of the Top Radiator Hose - Has a very sharp turn coming off of the
thermostat if that matters.

(1) of the Temp. Probe for the fan relay switch about half way up the
radiator. One other thing to note in this pic is that to the right is the transmission cooler - blocking/covering just about the entire front of the radiator with about a 3 inch gap between them.

Ben in Austin

 

Ford has a small thermostat bypass hose that runs from the intake water crossover just behind the thermostat housing down to the water pump. Many people mistakenly put pipe plugs in the holes and get rid of the hose, only to cause erratic temp fluctuations. Make sure you have that hose hooked up correctly

 

Do you have a multi meter? Can you measure voltage to the fan when it is running? Possibly if the wiring is too light of gauge you won't get the CFM you seek. I don't think it should be below -1.5V from the alternator output voltage.

How tight does the fan shroud seal to the radiator? If the gap is 1/4" I might try using sheet metal edge trim to fill the gap against the radiator.

Where does the AC condenser fit between radiator and trans cooler?

Do you have an IR temp gun? It'd be nice to calibrate the temp gauge. Another way to calibrate is to drop the sender in boiling water. It should read 212F :-). Note, you have to ground the sender threads to the engine or chassis to get it to close the circuit with the gauge.

 

Not for a capillary type sender driving a fan controller.

 

Hey 55,
Hmmmm... Not sure I remember a hose running from up by the thermostat. I'll have to investigate that one.

Doug - I do have a multimeter. I'll have to look at the wiring tomorrow.
So your assertion is that the fan may not be turning as much as it should due to wiring voltage issues. Could be - I have had problems with a couple of blown fuseable links - before getting frustrated & "rigging" the fan to just run all the time.

Thx
Ben in Austin

 

I'm talking about verifying the dash gauge temp readings. Are we certain those are correct?

Doug

 

Hey Doug,
I'll have to get one of those Harbor Freight temp. lasers to independently check the temp. I've got newer Autometer gauges.

55 - We do have a hose running from under the thermostat down to the waterpump - so at least a check mark for that one.

Let me come back to the transmission cooler for a second. I don't commonly see one of these on my modern cars. I don't plan to do any racing - is a separate transmission cooler necessary for our 351W/AOD set up? The transmission cooler is pretty substantial - covering virtually the entire front surface of the radiator.

Continuing to learn..

Ben in Austin
1950 F1

 

Doesn't your radiator have hookups for tranny cooler lines in the lower tank? That is all the tranny cooling/temp regulation you should need. An additional external fluid to air heat exchanger is overkill unless you are pulling a trailer/heavy loads. An air heat exchanger should NOT be the only tranny cooling it will not regulate the operating temp, the tranny will run hot or cold depending on the air temp. If the fluid smells burnt and/or is dark you have an overheating problem. If you don't have an internal tranny heat exchanger in the radiator you should give VERY serious consideration to changing the radiator. It will still be a lot cheaper than a tranny rebuild.

 

Hey Ax,
Yes our radiator has the hookups for transmission cooler lines down low & it also has a huge external cooler set up right in front of our radiator. We aren't doing any towing. I'll check the trans fluid for color/smell etc. in the morning.

I did not set up the AOD trans. - we had a shop do this part after having
some mechanics fail on the initial attempts. This external cooler looks like overkill to me as well.

I'm also going to re-wire the fan back to the normal fan switch relay set up & ditch the direct ignition "stop gap". Thanks for the help - I really appreciate it - this overheating problem has been bothering me for a while. It's keeping us from driving the truck as much as we'd like during the summer.

Ben in Austin

 

Ben,

It is hard to tell in your pics, but it looks like your upper radiator hose loops up before dropping back down. If it goes above the rad port on the top, it could get an air bubble in it and stop you from getting full flow.

Just a thought,
Dave