My 66' has a 351w in it( 74'-79' model). It's been running great with no issues. Then the other day it started to over heat. Temp would get to around 220-230 then go back down to 185-190 and back up to 220 or so, kept going back and forth. I changed out the thermostat and the same thing happened. So, I replaced the water pump and Radiator(cause I accidently put a nice hole in the radiator taking it out)....
So, New thermostat, new radiator and new water pump. still runs hot just idling(no running up and down the road). The old brittle shroud broke and I have yet to replace it. I did remove the new thermostat and that made no changes to the rising temp.
Any ideas on why all of a sudden my truck decides to run hot? Can a new shroud really make all the difference? I would think even without the shroud it would not run hot just idling... but I'm novice mechanic. The guy at the parts house measured my Radiator and sold me one the same size that fits a 79' ford truck which matched mine "almost" identically.


Any help is appreciated.

Thanks,

David

 

You'd be surprised at just how much a shroud does.

 

And how much heat gets generated under your hood when your sitting at idle.
When your truck is moving. The heat goes away quicker.

I wonder if one of your radiator hoses collapses when it gets hot? Old and weak.

 

Could always verify the new thermostat is working as it should. Seen a lot of parts store replacements being faulty out the box. A shroud is really good to have it plays a big part in cooling it down. It still has a mechanical fan not a clutch right?

 

If the system is pressurized, you aren't going to collapse a radiator hose.

I would try an aftermarket temp gauge to see if you are overheating.

 

I often wondered why they put those stainless steal coils in the lower (suction side) radiator hose years ago.
I guess it had nothing to do with hose collapsing. But I bet it helped when they got older. If they weren't corroded away.
But I have seen hoses collapse.

 

David, I have been around these trucks since they were new, they have a few ideos that you have to deal with one way or another.

You can not fill the gas tank and park it out without the sun heating and expanding the gas causing it to run out the filler. You have to not let the rubber hose between the tank & filler dry rot or gas will stink up the cab. You can not let these ol boys sit and idle in the hot temps, without them overheating. You can either keep them moving forward, idle them up, or shut them off. Leave at least 2-3" of air space in the top of the radiator or it will boil it out to get it. The system has about 4.5 gallons in it so a cup or two at the top is alright.

You can also spend money on shrouds, fans and other items or be the manager of the truck.



John

 

If the water level remains constant, suggest pull dipstick for cloudy oil. Also check fan belt alignment and tension. A faulty radiator cap (not holding pressure) can cause engine overheat. The water to anti freeze may be too rich, believe should not be over 50/50. And then there's the timing?? Fan shroud is handy but should not be the cause for over heating. Anyhow, couple suggestions of food for thought?

 

These trucks did not come with a fan shroud originally, it was probably added when the engine was swapped.

If it's a FoMoCo shroud, will have an ID engineering number marked on the upper left corner.

The following shroud will bolt on without any mods: D3TZ-8146-C (replaced C8TZ-8146-K), marked on upper left corner: C8TA-8146-S or D3TA-8146-DA

Original applications: 1968/76 F100/350 360/390 with standard, xtra cooling & A/C radiators. NOT used with Super Cooling radiator.

Reproduced by Dennis Carpenter.

 

Thanks for all the replies guys,
Rusbukt, New hoses all the way around.
87Bronco, Yes it's a mechanical fan. And YES I do have an aftermarket temp/amp/oil guage on it. It's an old sunpro unit. Likely installed when the motor was put in. Seems to work well.
Jowilker, I definitely need to replace those short little rubber hoses on the gas tank inside the truck.
Dave, Water level remains constant, No cloudy oil. Fan belt and alignment are correct.
Number Dummy, There IS a part number on the lower left side. D2-TA-8146-FA.... I'll check it out. There is a 4 inch thin metal plate than runs down the entire length of one side. It allows the shroud to be offset. I was hoping maybe I could find a unit that would discontinue that plate.

Thanks again guys and i'll keep you updated..
Oh. I sprung a hinge on my hood yesterday... UGH! I knew it was going bad.

 

D1TZ-8146-E .. Fan Shroud / Marked D2TA-8146-FA / Obsolete

This is a fan shroud for a 1971/72 F100 302 with Standard Cooling.

Since the ID engineering number for ALL fan shrouds is located at the upper left (drivers side) corner, someone rotated it so it would fit.

 

Check the top and bottom if the radiator with a temp gun and the spot where your temp gauge plumbs into...is it really overheating or do you have a faulty sending unit or gauge.

 

I was in o'reillys the other day and they have radiator caps with a temp guage built in so you know the actual temp of the coolant also considering all the stuff you replaced and it still runs hot might be a good idea to run a compression check on the cylinders

 

Thanks for all the info guys... I used some stuff called "Plastic Welder" to fix my fan. That stuff works pretty darn good. Got the fan back on and all is ok. Ran the truck for about 15 minutes and it never got above 110. Guess I can go ahead and put my thermostat back in I would never have believed a shroud could make that much difference. I'll be keeping an eye out for a new fan. But for now, I'm ok. Well.... accept for the hood hinge that sprung and broke on me yesterday!! UGH!!


Ps, Numberdummy, This one on ebay Would work with my metal extension....but a little pricey-
71 72 F100 302 w Standard Cooling RARE Ford D1TZ 8146 E Shroud Fan | eBay

This one would work. But I would have to turn it upside down. No extension needed.

Thoughts???
Ford Fan Shroud - D3TZ-8146-C - C&G Ford Parts

 

D1TZ-8146-E is available NOS .. You'll have to call the sources and ask how much.

NOS PARTS SOURCE in Olathe KS has 1 = 913-220-5746.

NOS PARTS LTD in Waxahachie TX has 1 = 972-937-2201.

CARPENTER NOS OBSOLETE PARTS in Concord NC has 2 = 800-476-9653.
-----------------------------------------------------------------------------------
D3TZ-8146-C is reproduced by Carpenter, many other repro parts sellers also have it.

I see no reason to buy it from a supplier in SoCal (Escondido is 30 miles north of San Diego), then pay extra shipping charges to MS since it's available in NC