Old Henry
Well-known member
This weekend we (wife, dog, me) did an overnight road trip that went from 101 deg. at 5,000 feet to 71 deg. at 10,000 feet. Learned some stuff about driving flatheads in heat. Here's what I learned:
Tailwind = hot. Started out going north on the freeway. Was cruising along nice, seemed more quiet than usual but my feet were getting hot, looked down at the temp guage and it was pegged past "H" and I wondered, "What the . . . ?"
Then I looked up at the thermometer above the rear view mirror and it was 101 deg!
I knew it was a hot day but that was hotter than I expected.
I wondered why every thing was so hot until I turned to go west and had the wind come in my window at me and the temperature dropped a little. Then I looked at all of the trees along the road and we had been going with the wind that reduced the air going into the radiator enough to cause the engine to get a lot hotter than I expected.
"H" doesn't mean the water's about to boil. We were taking the same trip we took 4 years ago to Bear Lake in northern Utah. On that trip when the temperature gauge hit "H" I panicked and pulled off the road at the nearest source of water to cool the engine down. Since then, I've learned a lot about engine temperatures, water temperatures, boiling temperatures, and pressure such that I was quite confident that the water would not boil out even though the gauge was pegged past "H". It pretty much stayed pegged past "H" for the next couple of hours until we climbed to a higher and cooler elevation. When we stopped for gas I measured the temperature of the top of the radiator (best indicator of coolant temperature) and it was only 202 deg. Nothing near the 222 deg. it would take to boil the water out at my elevation with a stock 4# radiator cap.
When the water coming out of the top of the engine was 202 deg. the heads were hotter - 210 on the left
and 215 on the right.
But those head temperatures didn't matter so much as the water temperature since that's what we gotta keep from boiling out.
"H" does mean the gas will boil. Although the water never boiled out with the gauge on "H", as soon as it hit that temperature the gasoline vaporized in the fuel pump and it quit pumping the gas. I'd had enough bad experience with such "vapor lock" to have installed a backup electric fuel pump back by the gas tank that I just switched on and carried on.
Stop lights mean vapor lock. When my temperature gauge got down below "H" I could switch off the electic pump until I came to a stop light or turned the engine off for a few minutes. Then, with no air moving through the engine compartment the gas in the mechanical pump would quickly boil and I'd have to turn the electric pump on just until I got moving again when I could turn it off.
Moving air does not cool dry surfaces, especially hot air. When it was 101 deg. outside (and inside) I tried for a while to cool off by directing the outside air directly on me by turning the vent window all the way in. After a while I realized that it was not working. The air was so hot coming in that it kept my skin totally dry such that there was no evaporation and no cooling. The hot air blowing on me was just making me hotter, not cooling me down. I was cooler when I shut the window until I was sweating just a little then letting just a little air in to blow on me and cool me down. The breaking point seemed to be at about 90 deg. Air blowing in below 90 seemed to cool me but air blowing in above 90 just dried me out and heated me up more than cooled me down. I had the thought toward the end of the trip that a spray bottle with water in it would have come in real handy to spray on us to help keep us cool. Maybe next time.
Less is more (air, that is). Relative to the previous point, when I realized that the blast of hot air coming in my vent window was too much, I turned the vent window from the other side in to direct air on me that worked much better at a lower volume because it was just the right amount to let me perspire just enough that the moving air cooled me down.
Keep your feet back. I mentioned that my feet were getting hot at the beginning of the trip. Here's why. The angled part of the floor was 117 deg!
So, I drove most of the way using the throttle knob to control the gas so that I could keep my feet back by the seat and off of the hot floor. (I have insulation under my floor mat. It would have been even hotter without that.)
Wear gloves. I usually wear gloves to drive anyway because it gives me better traction on the steering wheel, pads my left hand that's usually on the suicide knob base, and looks cool. But, on this hot trip the gloves were even more important because the steering wheel got so hot. The horn button was 103 deg!
I think that was a little hotter than the steering wheel itself because the bottom end of the steering column gets heated up in the engine compartment and transfers that heat up to the wheel hub.
Even the dash board that wasn't even in the sun was 106 deg!
Slower is cooler. On the last leg of our trip I got behind a motor home that was only going 55 instead of the 65 I had been holding. I decided to stay behind him since I was in no hurry. I noticed that after not very long my temperature gauge dropped noticeabley, probably down into the 180 deg. range, at the lower speed. When I finally got tired of that speed and passed him and went back up to 65 the gauge pegged past "H" again.
You might ask, "Why don't you get one of those swamp coolers that hang out the window?" Here's my answer to that. I have had quite a bit of experience with those and this is what I learned:
We used one for years in our first car - a VW Bug. It worked great for two reasons: 1. It was a very small space to cool, and 2. The car was airtight such that with just a vent window cracked open a vacuum was created that sucked the cold air in the through the cooler and cooled the whole car very nicely. We used it in mid-summer trips through southern Arizona and Mexico very comfortably.
But, then, we got a bigger car - an old Jeep Wagoneer. Maybe one of the funnest cars we ever had, but no A/C. So, we tried the swamp cooler with it. Didn't work for both of those reasons: 1. The space to be cooled was too big. 2. The vehicle was not air tight enough so that when a vent window was open creating a vacuum, hot air came in all of the holes and cracks and cancelled out most of the cool air.
I figure my big old Fordor Sedan would be much more like the Wagoneer than the Bug. It has a lot of space in it and it is no-where nears air tight. I know because when I get too hot in the winter I just crack the vent window open and can feel cold air coming in around the doors and around the back seat from the trunk.
Plus, gotta lay out around 600 smackers for one of those swamp coolers now. Not worth it.
When I was a kid we used to drive 'cross country in the hot summer from Utah where we lived to southern Arkansas where my mother was from without any A/C and just the windows open. I still have some flash backs of those great times when I'm driving "Old Henry" on a road trip in the really hot summer. So, that's why I do it. It takes some effort to constantly be adjusting the throttle, the fuel pump switch, the cowl vent, the roll up and vent windows, and drinking lots of water to replace what I lose. But, all in all, it must be worth it because I keep doing it.
Now the cool part: Heading up to Bear Lake we climbed 3,000 feet and, of course, as we went up it got cooler and cooler until it was down to about 75 deg. That, of course, was a perfect temperature to be cruising along up the green canyon by the river until we went over a pass at 8,000 feet and reached Bear Lake at 6,000 feet.
At the southern end of Bear Lake is a little town called Lake Town, pop. 187, that has this great old vintage service station still in operation.
Then we headed south east and came to the little town of Randolph, Utah , (pop. 476) where all of the record low temperatures for Utah are recorded in the winter, and we spotted this little store that claimed to be "The Smallest Store in Utah."
It was run by a man from Salt Lake City that brought his family up in the summer to run it.
They spent the summer living in what that claimed was the smallest house in Utah behind the store.
From Randolph we went south to Woodruff, Utah, (pop. 184) that was having a car show then turned west to go back over the mountain pass over 9,000 feet before descending back into Salt Lake Valley where the temperature was, again, over 100 deg. for the ride home.
Tailwind = hot. Started out going north on the freeway. Was cruising along nice, seemed more quiet than usual but my feet were getting hot, looked down at the temp guage and it was pegged past "H" and I wondered, "What the . . . ?"
Then I looked up at the thermometer above the rear view mirror and it was 101 deg!
I knew it was a hot day but that was hotter than I expected.
I wondered why every thing was so hot until I turned to go west and had the wind come in my window at me and the temperature dropped a little. Then I looked at all of the trees along the road and we had been going with the wind that reduced the air going into the radiator enough to cause the engine to get a lot hotter than I expected.
"H" doesn't mean the water's about to boil. We were taking the same trip we took 4 years ago to Bear Lake in northern Utah. On that trip when the temperature gauge hit "H" I panicked and pulled off the road at the nearest source of water to cool the engine down. Since then, I've learned a lot about engine temperatures, water temperatures, boiling temperatures, and pressure such that I was quite confident that the water would not boil out even though the gauge was pegged past "H". It pretty much stayed pegged past "H" for the next couple of hours until we climbed to a higher and cooler elevation. When we stopped for gas I measured the temperature of the top of the radiator (best indicator of coolant temperature) and it was only 202 deg. Nothing near the 222 deg. it would take to boil the water out at my elevation with a stock 4# radiator cap.
When the water coming out of the top of the engine was 202 deg. the heads were hotter - 210 on the left
and 215 on the right.
But those head temperatures didn't matter so much as the water temperature since that's what we gotta keep from boiling out.
"H" does mean the gas will boil. Although the water never boiled out with the gauge on "H", as soon as it hit that temperature the gasoline vaporized in the fuel pump and it quit pumping the gas. I'd had enough bad experience with such "vapor lock" to have installed a backup electric fuel pump back by the gas tank that I just switched on and carried on.
Stop lights mean vapor lock. When my temperature gauge got down below "H" I could switch off the electic pump until I came to a stop light or turned the engine off for a few minutes. Then, with no air moving through the engine compartment the gas in the mechanical pump would quickly boil and I'd have to turn the electric pump on just until I got moving again when I could turn it off.
Moving air does not cool dry surfaces, especially hot air. When it was 101 deg. outside (and inside) I tried for a while to cool off by directing the outside air directly on me by turning the vent window all the way in. After a while I realized that it was not working. The air was so hot coming in that it kept my skin totally dry such that there was no evaporation and no cooling. The hot air blowing on me was just making me hotter, not cooling me down. I was cooler when I shut the window until I was sweating just a little then letting just a little air in to blow on me and cool me down. The breaking point seemed to be at about 90 deg. Air blowing in below 90 seemed to cool me but air blowing in above 90 just dried me out and heated me up more than cooled me down. I had the thought toward the end of the trip that a spray bottle with water in it would have come in real handy to spray on us to help keep us cool. Maybe next time.
Less is more (air, that is). Relative to the previous point, when I realized that the blast of hot air coming in my vent window was too much, I turned the vent window from the other side in to direct air on me that worked much better at a lower volume because it was just the right amount to let me perspire just enough that the moving air cooled me down.
Keep your feet back. I mentioned that my feet were getting hot at the beginning of the trip. Here's why. The angled part of the floor was 117 deg!
So, I drove most of the way using the throttle knob to control the gas so that I could keep my feet back by the seat and off of the hot floor. (I have insulation under my floor mat. It would have been even hotter without that.)
Wear gloves. I usually wear gloves to drive anyway because it gives me better traction on the steering wheel, pads my left hand that's usually on the suicide knob base, and looks cool. But, on this hot trip the gloves were even more important because the steering wheel got so hot. The horn button was 103 deg!
I think that was a little hotter than the steering wheel itself because the bottom end of the steering column gets heated up in the engine compartment and transfers that heat up to the wheel hub.
Even the dash board that wasn't even in the sun was 106 deg!
Slower is cooler. On the last leg of our trip I got behind a motor home that was only going 55 instead of the 65 I had been holding. I decided to stay behind him since I was in no hurry. I noticed that after not very long my temperature gauge dropped noticeabley, probably down into the 180 deg. range, at the lower speed. When I finally got tired of that speed and passed him and went back up to 65 the gauge pegged past "H" again.
You might ask, "Why don't you get one of those swamp coolers that hang out the window?" Here's my answer to that. I have had quite a bit of experience with those and this is what I learned:
We used one for years in our first car - a VW Bug. It worked great for two reasons: 1. It was a very small space to cool, and 2. The car was airtight such that with just a vent window cracked open a vacuum was created that sucked the cold air in the through the cooler and cooled the whole car very nicely. We used it in mid-summer trips through southern Arizona and Mexico very comfortably.
But, then, we got a bigger car - an old Jeep Wagoneer. Maybe one of the funnest cars we ever had, but no A/C. So, we tried the swamp cooler with it. Didn't work for both of those reasons: 1. The space to be cooled was too big. 2. The vehicle was not air tight enough so that when a vent window was open creating a vacuum, hot air came in all of the holes and cracks and cancelled out most of the cool air.
I figure my big old Fordor Sedan would be much more like the Wagoneer than the Bug. It has a lot of space in it and it is no-where nears air tight. I know because when I get too hot in the winter I just crack the vent window open and can feel cold air coming in around the doors and around the back seat from the trunk.
Plus, gotta lay out around 600 smackers for one of those swamp coolers now. Not worth it.
When I was a kid we used to drive 'cross country in the hot summer from Utah where we lived to southern Arkansas where my mother was from without any A/C and just the windows open. I still have some flash backs of those great times when I'm driving "Old Henry" on a road trip in the really hot summer. So, that's why I do it. It takes some effort to constantly be adjusting the throttle, the fuel pump switch, the cowl vent, the roll up and vent windows, and drinking lots of water to replace what I lose. But, all in all, it must be worth it because I keep doing it.
Now the cool part: Heading up to Bear Lake we climbed 3,000 feet and, of course, as we went up it got cooler and cooler until it was down to about 75 deg. That, of course, was a perfect temperature to be cruising along up the green canyon by the river until we went over a pass at 8,000 feet and reached Bear Lake at 6,000 feet.
At the southern end of Bear Lake is a little town called Lake Town, pop. 187, that has this great old vintage service station still in operation.
Then we headed south east and came to the little town of Randolph, Utah , (pop. 476) where all of the record low temperatures for Utah are recorded in the winter, and we spotted this little store that claimed to be "The Smallest Store in Utah."
It was run by a man from Salt Lake City that brought his family up in the summer to run it.
They spent the summer living in what that claimed was the smallest house in Utah behind the store.
From Randolph we went south to Woodruff, Utah, (pop. 184) that was having a car show then turned west to go back over the mountain pass over 9,000 feet before descending back into Salt Lake Valley where the temperature was, again, over 100 deg. for the ride home.
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