Hot weather

[G.M.]

With what looks like a long hot weekend comming in a lot of the country let's try and get some reports on heat related fuel problems with the old and new types of gas. Here's some of the data that would help.
1 type of gas
2 out side temp
3 temp of top part of fuel pump
4 " fuel bowl on carb the where full is stored. (Needle valve area)
5 " at base of carb above intake manifold
6 " on intake below the carb
7 " on both heads, hump behind W/P 32-36 center hose outlet 37- 48 and goosenecks on 49-53
8 fuel pressure if available As fuel temp rises, fuel pressure drops.
9 type of intake manifold, steel or aluminum
10 plain fuel pump or with glass filter bowl

There are going to be more and more problems as it gets hotter and maybe we can provide some help before it gets people stuck on the road.

I haven't had time to take my 39 P/U out for a good test drive after working on it a few weeks ago. It was 92 plus today, a good day for it.
I reduced the heat riser holes to .325 , installed a [email protected] 1/2" vented carb spacer and a pressure gauge in the fuel line between pump and carb. I also installed gadgiteers 180 degree high flow stats in the upper hoses at the radiator. Went about 6 miles today and it was at 180 on the gauge. Drove 25 miles at 60 mph stopped checked temps.
Pump 116
carb at fuel bowl 112
bottom of carb 107
top of steel intake 180 (with heat riser holes reduced)
Both heads at hose oulets 178 to 181 If the red laser dot is moved
1/2" you will get a 1 or 2 degree change.
Fuel pressure 2 1/2 lbs Fuel pressure was 2 3/4 at cold start up.

After lunch water temp was 160. Started as so as the starter turned.

Headed home with a few short stops, temp gauge 180 at all times. Motor really likeing 180, smooth. Back at shop all temps the same as when we stopped for lunch with fuel pressure at a steady 2.5

This pick up has Skips pumps, 6 bladed industrial fan and a shrowd. The hot air don't get trapped at the rear of the engine like my 39 convertiblewith the crankshaft mounted fan and no place to discharge hot air. This truck has the generator mounted fan blowing air over the engine and side hood vents that let hot air out. Stay coool and please get me some info. G.M.

[PeterC]

" 6 bladed industrial fan and a shrowd. The hot air don't get trapped at the rear of the engine like my 39 convertiblewith the crankshaft mounted fan and no place to discharge hot air. This truck has the generator mounted fan blowing air over the engine and side hood vents that let hot air out."

G.M . - With your 39 - doesn't the hot air get forced down the firewall and blown out the bottom? Also - do you run splash pans and does that hurt or help the cooling? I never had a cooling issue with my 39 and I running a big bore / high compression flathead.

[G.M.]

Peter you live in Conn not Florida and how much driving have you done in 90 plus weather?? The ambiant temperarature is main factor, this is the base of the problem plus engine coolant temp. One thing that has to be described is what is hot?? A lot of posters on this site promote over 200 and higher radiator pressures running down the road. I don't want to ever see 200 on my gauge that's getting to the danger zone as far as I'm concerned with no cushion if you get into stop and go traffic on a hot day. I'm holding a temperature of 180 steady at all times with Bob Shewman's high flow thermostats when it's over 92. In the old days we didn't know what temperature the engine was all we knew was when it boiled over it was hot. This mentality has been carried along with some. The fans on most of these old Fords don't do the job. Forward motion air is what provides most of the cooling through the radiator. High temperarues make it uncomfortable in the vehicle, causes the engine to use more oil, lower oil pressure and gas boiling problems. On the 39 type CARS the crankshaft mounted fan blows the air against the front of the engine, I never attempted to track the flow after it hits the engine. Small strips of ribbon placed in the area will show the air flow if you are interested. I do have the engine pans on mine but I doubt they do much if anything as far as cooling. They are called slash pans and I assume that's their function. Exactly how the air flows is just a guess but the fan air hits the block and go's down and off to the side. I would guess the now warmer fan air from the radiator would go off to the sides and some out the bottom along the fender, frame area. Not much is going up over the engine because the radiator sits low. A small amount go's over the radiator and this wouldn't do much. There is a lot of heat on top of the engine from the heat riser temperature in the intake, this is a big problem even with the heating of the fuel pump. A stock aluminum intake is worse than a steel one. The rear of the heads and the exhaust manifolds heat also rises right up the fire wall. The temperature of the firewall gets over 135, the clip that holds the fuel line to the firewall heats the fuel line to over 135 which is right about the boiling point of this new gas. The fuel pump gets even hotter from the intake and rear engine heat. At this point the fuel boils and the fuel pressure drops down to where it don't pump. The heat from the rear up in the area from the air cleaner to the fire wall is all trapped there with no air motion to move it, heat rises and there are no openings for it to excape. I have measured over 135 in this area AFTER the hood is opened. I took 3 peices of 1/4" rubber hose about 3"s long and slit them down one side. I put them over the rear edge of the hood, one in the center and the other two maybe 10"s from the center one. This gives a little slot for air to excape, keeps the hood tight and is not real noticeable. Calling for 94 down here today. G.M.

[JM 35 Sedan]

George, I'm planning to take some temperature readings on my '35 fordor engine during these upcoming 90°+ days. I bought some carburetor insulators/heat shields from the coolcarb guy in Red Lion, PA. Have also talked to him about maybe making a special fuel pump insulator/heat shield that would space the FP up off the intake manifold and also provide a heat shield that would extend under the glass bowl.
Are you up in PA now? If so I would like to ride up to your place one day in the next couple weeks if you plan to be around. Could you send me a pm or an email on which day might be best for you. Thank you!

[Shadetree]

I haven't had a chance to get my `35 out in this 95° weather. I have worked three days a week for the last four weeks. We went to the Indianapolis car auction on Thursday, got home on Saturday, left for my Myrtle Beach Air Force Reunion Sunday, got home Thursday, went to my granddaughter's graduation last evening and mowed grass today. Tomorrow we make our annual trek to the cemeteries. Maybe Monday being a holiday I can relax and play a little.

But I wanted to mention this. A couple of weeks ago I saw a five bladed flex fan at NAPA that looked great. The bolt pattern looks close and I think with some ingenuity might work on our some of our old Fords.

[G.M.]

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shadetree I have seen the flex fans for years but the look of them turns me off. You can some thing that looks like it belongs there. Pictured is an industrial 6 blade I modified for the 39 P/U and my 35 roadster. This fan works perfect. Need to find a fan manufacture to make them.
John I won't be up until after the 25th of June. Email me, I don't fool with the PM much. I only answer them except ones from Ct. G.M.
Tried to add the fan picture several times but it don't want to come up.