Hello all,

So I have a '77 F250 with a 351 and a C6, and I live in Yuma, AZ. PO has converted the mechanical fan to dual electric "Puller" fans from a dodge minivan. decent amount of air away from the radiator, but driving highway speeds for about 45 minutes causes the engine to over heat. After several flushes of the radiator, I've cleared it of what looked like muddy creek water,(all of which i'm sure in my engine..) which helped it last longer between overheating, but if I try to go 65+, it will climb up to the top edge of the temp gauge within minutes. The truck doesn't use the trans cooler in the radiator, it uses an external wired to the back of the radiator, with the AC condensor mounted to the front. All of my fins are clear, and save a few small dings on the trans cooler, all are undamaged.


What's the best route to keep temperatures in a safe range?

 

Have you checked that the thermostat is opening completely?

 

Your truck came w/a fan shroud originally, is it still in place? Shroud is reproduced, available from Carpenter.

People make the mistake of installing the thermostat (t/stat) backwards, will take a looong time to open if this has occurred. T/stat element is supposed to face towards the engine.

351M/400 t/stats are a different diameter than any other engine size. Factory installed, it was 197 degrees. A 180 t/stat was available at the parts counter.

 

Shroud is gone, It came with the truck when i bought it, but it was broken beyond useability, however electric fans are mounted to the rear of the radiator in place of the shroud/mechanical fan setup.

I'll have to check the thermostat, it's probably also caked with garbage, or bad.

 

I had that same muddy creek water affect in mine too, lol. I ended up flushing it 5 times, 2 days of driving to and from work, inbetween. I know AZ is not cold enough for a heater, but run the heater to get any sludge out of the whole system. And as Number Dummy says, might as well change the thermostat, cuz its probably stuck too.

I ran my truck for 3 days without the shroud, but i went to work at 5am, got home at 6pm, and only 10 minutes to work. The first day i drove in traffic, my overflow bottle lid blew off and filled the engine compartment with antifreeze. I put the shroud on and temp stays at the "R" in Normal...

Heres what happened, the PO replaced the original fan for a mini van electrical fan because he didnt know where, or didnt want to find out where to get a shroud. I have had and worked on minivans, no way do those fans suck as much air as the correct OEM setup, lol.

 

It snows in parts of Arid-Zona like it does here in parts of CA

In winter, it can be colder than a witches teat in Bisbee, Show Low, Flagstaff, and etc.

 

Hahaha, that little emoji thing is amusing...when it's in someone else's comment quote. Im starting to loathe it...

 

Definitely doesn't snow in Yuma, I'm five miles away from the Mexican Border. I'm looking into going back to the mechanical fan and shroud setup, although $120 for a new shroud seems pretty steep.

Since it's already wired for an electrical setup, and that seems to be a popular swap anyway, a bigger fan should solve things right? Something out of a newer V8 truck? I could probably score a new fan for $50 at the junkyard.

 

It cant hurt me to try, right? I say go for it! Keep us posted as to what donor truck you get it from and how it works out. You may be able to help someone else, or steer them away from something.

 

Grab yourself a Lincoln Mk VIII two-speed fan. The shround covers 90 percent of the radiator surface. It'll suck a cat flat to the grill....



Here are some links for background info:

Electric Fan/Cooling Upgrades
Ford Muscle: Lincoln Mark VIII Retrofit
Fordification Thread: Lincoln Mark VIII/T-bird Two-Speed Fan Installation
Pro-Touring.com Thread: Mark VIII fan & SPAL Controller
Hollister Road Electric Fan Components
The Fan Man - Electric Fans & Controllers
Nasty Z28 Thread: Budget Dual Electric Fan Controller Set Up
FTE Thread: akforceten's 1972 F250
Centech Fan Controllers

 

Oh yea, prove it.......no harming of real live cats during the attempt, are allowed. lol

Maybe the fact you were going 110 MPH when ol Frisky tempted life #9 with that dive to follow Mr Whiskers across the road is why it stayed there?

You know the rules.

 

Good morning Rich. How are things in the former Soviet Union? Brrr!

C'mon now, it's a figure of speech.....a colloquialism.

 

I'll attest with a markIII fan running full on and parked you can feel the air being pulled into the radiator standing in front of the truck. It kept the mild 460 in my truck cool at 104* in bumper to bumper traffic no problem.

 

Yes I know you were kidding...I just wanred to see a cat stuck to your radiator. And I like being the resident funny guy at times.

Still cold here and I'm counting the days till I can get back to my projects....I need a long break from work this time.

You know most normal folks in the US are asleep about this time, or are we just getting in from the bar? Its 12:30 PM Sun here, I just got done with lunch.

 

Nope I'm no bar fly, I work nights. If I have nothing going on except working on the truck, I stay on schedule. I'm about to have dinner in a bit .