Another interesting development. This morning, wifey and I took Ol' Furd out for breakfast. It's our Sunday morning ritual. Our breakfast place is about 10 miles out near the foothills on an open country road. It never got above 160°, which is puzzling since it has a 180° t-stat. So apparently the t-stat is stuck open all of a sudden like. Same thing on the way back. There are two stop lights and a stop sign as we approach the house. The furthest one out is less than a mile away. That furthest one was green so we breezed through. The second is a bit long winded. The temp climbed to 180° in the minute we were sitting there. Then to 190° between there, the last stop sign at our street and the time we pulled into the drive. All within the space of a half mile. For a minute, I thought the gauge was faulty. So, I reckon I add a quality t-stat to the list. At least it hasn't been boring.
The results are in. Twin electric fans are out, 17" Derale steel six blade fan with shroud are in. This year of F100 did not come with a shroud, so I built one using the twin fan shroud as the starting point. Another consideration is the engine location is offset to the p***enger side by a few inches, so the fan is not centered to the core support opening. The stock radiator was offset a like amount with a fill panel on the driver side. The aluminum radiator has full width of the core support opening, so the fan is not centered to the radiator core. I used a flat piece of metal attached to the water pump pulley to act as a comp*** to mark a circle the size of the fan on what was left of the shroud. Then a strip of .050" thick aluminum sheet was rolled to make fan surround, with about a half inch clearance, and the fan fully enclosed. Rather than just stick the surround on a flat panel, I made some dished panels so the fan could pull through as much of the radiator surface as possible. The finished piece will absolutely NOT win any appearance awards. I'm severely out of practice welding aluminum. But it's stuck together good and solid. I also had to make it two-piece because there was just no room to put it in with the fan, and no way to put the fan on with the shroud in place. So a detachable panel was the only solution. Once it was all in, I took 'er for a drive in town in the heat of the afternoon. Once it was up to operating temp, showing a bit under 190° on the gauge, it stayed there. It would eek up a couple degrees at stops, but come right back down once moving again with more fan speed.
As far as odd temperature readings go, might make sure your coolant level is correct. In my OT Dart which had a leaking heater core, there was not enough coolant for the temperature probe to get an accurate reading. It would read 160 after an hour plus of hard driving, with a 190 tstat. With the leak corrected & the coolant level holding where it should be it now reads correctly.
Thermostats are made to get engines to the proper temp faster....When they get above the tstat rating they are wide open and not controlling anything....
Yes they are... when they work right! I have tested some that either don't fully open, or when they ARE fully open, have a restricted area flow path. It always pays to test them first and not ***-u-me. A thermostat is not an item to go low-buck on!
I always remind people with heating problems, you need a way for the hot air to go out the back of the engine compartment and a panel between the hood and radiator so hot air can't come over the top of the radiator to the front and be drawn in as more Hot Air.
Champion Radiators sells radiator and fan combinations similar to yours, they have 12" fans that are rated for 850 cfm each. Thats not enough cfm for the heat we are have now. I know a guy with a '65 GTO with the same type of fans and shroud, his over heats very quickly when in traffic, the two small fans just cannot move enough air and the shroud blocks to much of the core when driving so it never really cools back down. Good idea using the water pump to draw the circle opening!
My thoughts exactly. If those fans are against the radiator the shroud does nothing. I would fit bigger fans again the radiator and ditch the shroud.
Mike, I have to respectfully disagree with you on your fan shroud. I think it looks fantastic and it works great as well. If you painted it black, the causal observer would think it’s factory!!
Thanks Andy! Design-wise, I am happy with it. It functions as well as I'd hoped. But yeah, I have seen factory stuff that bad. Worse in fact! Appearance wise....well, I reckon the "Booger Welds" bring it down a few notches. It was getting better as I went, but then I'd touch the electrode to the weld and there'd be a big booger at the end. At least I didn't blow big holes in it. I reckon if I yanked it out, ground the welds, smoothed it out and painted it wrinkle black, it'd look pretty good. If it wasn't such a ROYAL pain to R & R it, I would. But the job is done, it's working well, so it's on to the next. Thanks again!
Mike, at least you can weld aluminum and thin aluminum at that! If I were to build anything like that, my buddy Johnny at work would have to do the welding.
If you have Cataracts this could hinder you ability to see the welds. After I had my Cat. surgery which was easy my welds were so much better looking I could not believe the difference the surgery made.
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