Ok guys. I need some expertise knowledge here. So my 1954 F-600 I bought has a 1970 361 motor in it. When I bought it the cooling system was old and not working so good. So as you may or may not know it gets pretty warm here in the summer. Last year we hit 120 consistently. So knowing that and wanting to drive my truck year round I ordered a new aluminum radiator with dual electric fans, new water pump, new thermast, all new hoses and even a new temp sensor. I took it out yesterday for the first time since I installed all that and after driving it for about 20 min I noticed if I was stopped to long at a light or idling it would climb from 190-200 to over 230 pretty quick. Even in the cool 80 degree weather we are having now.
So my question is what am I doing wrong?? Or what can I do to prevent this??

 

You need a shroud that will cause the fans to pull air thru the entire core of the radiator.
You have the room, why not go back to an engine driven truck fan?
Edit, at road speed and not pulling a load, you would not need any fan.

 

One of the first things I would do, would be to get those fans mounted differently, get rid of those plastic ties thru the radiator, nothing but problems there. Mount the fans on a diagonal, on a fan shroud. If the fans are set to operate with a sensor check to make sure you have it set properly to come on at a lower temp. Are the fans push or pull, sounds stupid but ya never know. Timing, carb idle settings and faulty thermostat (I know you put a new one in) Just never know

 

both above posts are right on. Not enough air flow at idle, so make a shroud to cover the whole core which will also get rid of the plastic through the core mounts. Verify fans are wired to pull air, they can go both ways but only pulling air into the engine compartment is correct. Run a 180 thermostat and set the fans to come on at 190 degrees.

 

Were the fans running when the temps were climbing? What is the setpoint for the fans to come on? Are they set up to both come on at once, or staged?

 

The one fan doesn't look like it's hooked up..

 

I went through similar issues with my '54 when I bought it from cool northern coastal Calif, then brought to my home to the hot Sacramento summers. (Not quite heat like where you are at, but it can be disturbingly close.) Do all those things the above wise sages mention, first!

But, if you do all that and still have a problem, you could have the same stupid "possessed by Satan" problem that I had. I would show accurate temps (as it turned out) in the 180-190 range, but when in those times when you might normally get to 200, the gauge would show much, much higher. I chased that problem through a whole "barely could drive it summer" and beyond, with ridiculous amounts of downtime, research, work and $$ thrown at the problem.

I got so frustrated i decided to work on some electrical improvements instead, since i couldn't drive it much. Things like redoing all my grounds..........yep! a poorly grounded temperature gauge was the only problem I had

 

I would recommend the old school approach of mounting the largest engine driven fan on the water pump hub, fabricating a fan shroud that covers the entire radiator core and has about 3/4" clearance to the fan blade tips and has about 1/4 to 1/3 of the back of the fan blade sticking out the back of the shroud. Then if you still need more, consider electric pusher fans mounted on the front of the radiator. I know electric fans can move a lot of air, but look at the small area of radiator core they are acting on.

 

Hey Troy,
Hmmm... I live in Texas & it's hot. We had a similar problem ...I just couldn't get the truck
cooled down..just kept climbing... I like what the guys are saying above....but I would add a bit..

o These trucks come with a lot of metal pieces that fit around the radiator to make sure the
air flow is blocked on the sides, above, & below the radiator. If you don't have these pieces the
air flow isn't going where you need it.

o What CFM are your fans pulling? Not all electric fans are created equal. You could have some pretty
small weak fans. We installed the biggest electric fan we could find out of salvage - a Mark VIII Ford electric
fan from a V8 Tbird ...pulls 4000 cfm at the highest speed. I bet your's may be barely 1500 cfm. (Not enough air flow).

o The way these are set up ... you have a 2 speed temp sensor, a relay, etc... We gave up on the modern fancy set up & we turn our fan on with a
switch in the cab. Not fancy but It works.

o Having the right Timing is critical ... Running too lean on your carb is also critical. Get your timing right & your carb set a little rich.

o Thermostat in backwards? It's very easy to get the thermostat in there wrong with the spring on the wrong side. Is the upper hose getting hot?
Is water getting through your thermostat? You can also check your thermostat on the stove in water to make sure it opens.

Good luck over there.

Ben in Austin
1950 F1

 

Hey thank you guys for all the good info. The small electric fans came with the radiator. I have them setup on a temp sensor to come on at 180. I have them setup to pull thru the front. I think I’m gonna build a front mount for those and then add the single bigger electric fan I had on the original radiator and build a shroud. See if that does the trick. I knew I could rely on you fellas for great advise. I’ll post pics of what I come up with.
Do any of you guys run without a thermastat? So the coolant is constantly flowing? I know here in the hell state we don’t have to worry about keeping the engine warm.
The pic is the original fan. Much larger.

 

Those electric fans look good. At what temperature do they come on? Is the rotation correct? You have them set up as pullers. If not just reverse the polarity.

I agree with gerrymoe, get rid of those plastic mount ties. They will damage your radiator.

And as Ray says you do need a shroud. I made a shroud/mount out of polished aluminum diamond plate (see picture below).


Plastic tie damage after less than 100 miles.


Fan mounted on a piece of polished aluminum diamond plate. Make sure that it goes all the way to the top and bottom. There is about a 3/4" gap between the fins and radiator which provides enough room for the air to flow to the fan. It works good.

Also that hose coming of the top of the pump is bulging and does not look good. I would recommend replacing it.

* * *

 

Ok fellas here ya go. I took all the advise I got and pulled the two small electric fans off the radiator and built a cowl from some spare steel I had and put the larger single electric fan back on. It worked like a charm. Drove it to work this morning and it never got over 220 degrees. Even stopped at lights and a long train.
Now I just gotta pull it back off and clean it up and paint it.
Thank you guys for all the great advise.

 

Looks good. To improve it you can add rubber flaps to the back corners of your shroud. It looks like you have a lot of room there. They will would suck against the shroud at stop lights and low speed forcing the fan to pull air through the whole core and at speed they allow more air flow through the radiator to keep temps in check.

In the attached link post #11 shows what I am talking about.
What to use for Flapper Door??

 

That looks good Troy.