Cab gets hot

[jmccrack]

174317

So here’s the deal. After driving for an hour or so the inside of the cab of my 35 gets very hot. As we all have done when we built these trucks we went to great lengths to make sure hush mat,foam and carpet covered everything. I have checked the fire wall it’s almost water proof (so to speak). The floor is an inch thick the ram horns and the collectors have been wrapped the mufflers have been wrapped. I think I need to get air into the cab from under the fire wall. If you look at the picture I sketched in a vent I was thinking of installing. I would have to machine it custom. Any thoughts from anyone?

[mkassab]

That should work, however, having restomoded a 51 Ford F1 Pickup that had an air-vent as you describe keep the following in mind:

1. If the air coming thru the new vent doesn't have an exit in the cab, it will just build a positive air pressure in the cab and won't achieve your intended purpose.
2. If open, watch for rain and bugs coming in.
3. If closed, you'll need a rubber weather seal and a rain catch culvert around the perimeter with a drain so water won't come into the cab (see pic below).
4. You'll need a latch system similar to the '51 ford that can latch the vent door tight enough to prevent air and water from coming in and to hold the vent door open.

Good luck, Mark

Summit Racing air vent link: https://www.summitracing.com/parts/upd-b20074?seid=srese1&gclid=CjwKCAjw5P2aBhAlEiwAAdY7dNcfizy_7FaIvM7FRtFN YnJ-tVGbWGRFewrN6nwqTNefee3ZcP6mXxoCxUIQAvD_BwE
https://thefactoryfiveforum.com/attachment.php?attachmentid=174321&d=1667220430

Picture of #3 above
https://thefactoryfiveforum.com/attachment.php?attachmentid=174322&d=1667220430

[J R Jones]

A potential conflict exists if you have engine ventilation (louvers) ahead of a cowl vent, or a poorly sealed hood. The engine compartment exhaust could get into the vent.
I fabricated my interior vents for the sides of the cowl with live hinges and a latch that doubles as a prop for open position.
jim

174325

174326

174327

[mkassab]

A potential conflict exists if you have engine ventilation (louvers) ahead of a cowl vent, or a poorly sealed hood. The engine compartment exhaust could get into the vent.
I fabricated my interior vents for the sides of the cowl with live hinges and a latch that doubles as a prop for open position.
jim



Jim, I wouldn't think any "exhaust" would be in the engine bay at all? May I ask why you say/think that? Also, with his plan on a cowl vent about the hood, even if the engine bay had exhaust, I wouldn't think any would enter the cowl vent/cab.

Just curious,
Mark

[J R Jones]

Mark,
Exhaust is not exclusively "products of combustion" (engine compartment exhaust); even your kitchen and bathroom fans have an exhaust.
The engine compartment air intake is through the hot radiator and swirls around engine, adding to the air temperature.
The heated air has to go somewhere. Likely it goes out the back, under the floor, but also through any louvers in the hood, as intended.
I have a 1929 Mercedes SSK replica Roadster; the engine exhaust heat vents through the hood louvers and goes over the windshield into the cockpit, with the top down. The side vents help to cool the cockpit.
jim

174350

[jmccrack]

Some really good thoughts here guys. Thanks a lot. Has anyone on the forum added vents to get air into their cab?

[Chris Wingardh]

174317

So here’s the deal. After driving for an hour or so the inside of the cab of my 35 gets very hot. As we all have done when we built these trucks we went to great lengths to make sure hush mat,foam and carpet covered everything. I have checked the fire wall it’s almost water proof (so to speak). The floor is an inch thick the ram horns and the collectors have been wrapped the mufflers have been wrapped. I think I need to get air into the cab from under the fire wall. If you look at the picture I sketched in a vent I was thinking of installing. I would have to machine it custom. Any thoughts from anyone?

Go to a muffler shop and have the mufflers move back, and run the pipes over the rear end. Tom Wallace did this and I will do the same once the truck is done. For now it is mounted where the manual says.

[Windsor]

Side vents?

Military trucks (specifically 2.5T and 5T trucks) from 60s to 90s had vents forward of the door hinges with "kick levers" to open them.

The openings had screens with holes smaller than 1/4" kept unwanted critters from coming in the cabin with the side vents open.