Are all cabs like an oven? (1 Viewer)

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My 79 40 is horribly hot. The floor and firewall put off so much heat that it is very uncomfortable. Is this just the way it is? I tried some 1/4" black poly type insulation and mats over the top. It helped some, but after prolonged driving it didn't make much difference. It's our only car and I gotta figure something out or the wife's gonna make me sell it!
 
The 40's came with little to no insulation from the factory and most just had metal floors. The heat you're feeling is from the engine and transmission. If you put your hand on the transmission tunnel you'll feel it's pretty hot.

Maybe dynomat and then vinyl or carpet would help the heat dissipate.
 
Do you have a header or modified exhaust that puts the pipe closer to the floor?

Can you put some heat shields along the top of the pipe?

Is the pipe under the floor routed correctly?

My '78 FJ45 does not get uncomfortably hot. But we do live in different climates.
It seldom gets to 90* here.
 
It's stock stuff but the heat shield idea is good. I wonder if spray-on insulation on the firewall would help or hold up under the heat and bouncing? The heat shield idea gives me another thought. A foil backed insulation glued on the underside of the tranny tunnel. If that works try the same under the floor pans.
 
It is what it is.

I remember meeting my first square-bezel factory AC 40 on the trail in 1988. The owner said he’d looked long and hard to find one with factory air. I asked him how he liked it.

He said it was good for being able to wheel dusty trails with the windows rolled up. But as for cooling, it made as much sense as trying to cool a toaster oven.

My ‘68 was ok until I bolted on the 2.5 Flowmaster exhaust system I got secondhand from @Mace. That turned the plastic container with my solderless terminals in my underseat toolbox into a popcorn ball! :eek:
 
For my money, the best results come from wrapping the exhaust. My exhaust is wrapped from the exhaust flange (headers) to the muffler. It significantly reduced the amount of heat under the floors.
 
First remove your heater...
20180324_183159-1008x756-jpg.1662093

Then take some heavy duty paper and make yourself a template. Tape all the pieces together, make your template go all the way to the top of the cowl. Make sure to do a good job with the template. Go around the steering shaft and everything. Once complete remove template that is all taped together and trace the template to the insulation, the stuff I got is held on the firewall with pieces of quality sticky backed velcro here n their. I did not use stick on insulation because if it gets rear wet you can remove it or at least pull it away a bit for it to dry out.
20180328_212841-1008x756-jpg.1665370

You can do the same thing to the floor and trans tunnel. Thats what I did. The insulation was bought on amazon and is about 3/8 thick and has reflective material on one side. Now I can touch the firewall and its barely luke warm. I added air conditioning too so its really nice in the summer now.
Here is the link for the insulation.
https://www.amazon.com/CSI-25070-He...2358809&sr=8-1&keywords=csi+25070&tag=ihco-20
 
Exhaust wrap is available at O'Reillys, Auto Zone, etc. Or you can order it from Summit Racing.
 
Just for the record, not all 40's are like an oven. In some regions of the country they are more like a blast furnace.
 
I have insulated the tunnel and floor with Reflectix and that helps, but after a couple hours of driving the heat suffuses any insulation and you're headed back to oven status.
 
With headers registering 450* and a desert registering well over 100* in summer, driving 44 was a miserable endeavor.

After driving home, thru Tonopah, in 108* temperatures and keeping ice under my dog’s belly, I decided I would never again make summer trips in 44.

I also decided I would see what I could do to mitigate the heat in the cab.

So, like others:


I removed my heaters and sold them to someone who would use them.

I insulated the floor, tranny tunnel and as high on the firewwall as I could, using https://www.amazon.com/Automotive-Constrained-Dampening-Deadening-Resonance/dp/B00C10TO8Q

YUGE difference!!

I’ve made numerous cool/cold weather trips and have never been cold.

I’ve made numerous warm/hot trips and been quite comfortable, windows and vents open... even while crawling.

I’ve never again driven 44 with temps over 100*... but, I could if I needed to get to Central Nevada mountains.

So, you can mitigate the cab heat.
 
With headers registering 450* and a desert registering well over 100* in summer, driving 44 was a miserable endeavor.

After driving home, thru Tonopah, in 108* temperatures and keeping ice under my dog’s belly, I decided I would never again make summer trips in 44.

I also decided I would see what I could do to mitigate the heat in the cab.

So, like others:


I removed my heaters and sold them to someone who would use them.

I insulated the floor, tranny tunnel and as high on the firewwall as I could, using https://www.amazon.com/Automotive-Constrained-Dampening-Deadening-Resonance/dp/B00C10TO8Q

YUGE difference!!

I’ve made numerous cool/cold weather trips and have never been cold.

I’ve made numerous warm/hot trips and been quite comfortable, windows and vents open... even while crawling.

I’ve never again driven 44 with temps over 100*... but, I could if I needed to get to Central Nevada mountains.

So, you can mitigate the cab heat.

Like it. I'm from Peoria/Avondale/Show Low. good tips. Thanks
 
I used CCOT insulation and a vinyl molded floor mat, plus A/C. I also patched every hole I could find in the firewall. I did this by putting a light undr the dash in a dark garage and laying under the car looking for light shining through. To be honest my rig is pretty comfortable in the summer. Patching all the holes kept a lot of hot air off of my feet.

Insulation ~ FJ40 Front Floor

FJ40 - Front Moulded - One Piece - Floor Mat
 
This was my quick and dirty solution before a Death Valley trip, a poor mans evaporative cooler. 2.5 gallon pressurized water fire extinguisher plumbed through a misting nozzle. I had it hooked up through the fresh air intake, but it worked best just pointed directly at the face. With windows down and travelling at highway speeds, it wasn't comfortable, but bearable, and the dry desert air kept things from getting wet.

This kept me alive when temps were 105+ and driving through the valley for hours at a time. The floor got so hot I actually burned my hand pulling out the bottle jack from under the seat. At times my feet were getting uncomfortably hot so I had to point the mist at my legs. One of these days I plan on insulating the firewall as much as I can, that would be the ideal solution


IMG_0583.JPG
 
Here in Oregon the heat isn't too bad. Open the kick vents, top off, and I'm good to go .. :)
Prob will eventually get new ac/heater for better efficiency and cooling.
 

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