Auxiliary heater

[rustystud]

Another winter project I've been working on is a auxiliary heater for the passenger side. Like my main heater it is shortened and will be mounted where the air filter is now. I recently bought a M35A3 air-filter housing which I will be installing later on. I still need the blower motor. I plan on getting the NAPA one #655-1320 .

 

[tommys2patrick]

Good looking work. What will your thermal source be?

 

[gimpyrobb]

Good looking work. What will your thermal source be?

Coolant from the motor.

 

[tommys2patrick]

will you use the same heat transfer box as the regular heater or did you have something else in mind? It does not seem to me that the original heater put out that much heat.

 

[gimpyrobb]

will you use the same heat transfer box as the regular heater or did you have something else in mind? It does not seem to me that the original heater put out that much heat.

Imagine the stock heater cut down to eliminate the empty space inside. Now imagine that he has one i stalled and this will be the second one, going in place of the stock deuce air filter. That is the system he is working on.

 

[tommys2patrick]

so---installing a wye into the supply/return water hoses to feed a second box then I imagine. Separate controls at the wye? in case you want to shut that heater or the other down?

I was wondering if anyone experimented with the idea of insulating the heat exchanger box or something along those lines to improve performance? perhaps not worth while??

 

[JasonS]

Up until recently, I had two heaters: a defrost unit and a fairly large Cat heater under the passenger seat. Worked excellent with the gas motor. Awful with the multifuel (same water temperature). The multi has a water pump much smaller than the gas engine and, near as I can tell, wasn't able to push the water through the series connected heaters. I have the A3 heater cut down under the dash which is an improvement. Will be curious how your system works out.

 

[rustystud]

Up until recently, I had two heaters: a defrost unit and a fairly large Cat heater under the passenger seat. Worked excellent with the gas motor. Awful with the multifuel (same water temperature). The multi has a water pump much smaller than the gas engine and, near as I can tell, wasn't able to push the water through the series connected heaters. I have the A3 heater cut down under the dash which is an improvement. Will be curious how your system works out.

The first picture shows the return port (lower left). The second picture shows my first heater mod. The third picture shows the outlet port for the second heater.
Since I'm using different ports to feed the heaters I should have plenty of heat. Also they are all before the thermostat. The returns lines are on the water pump suction side.

 

[rustystud]

I received my M35A3 air-filter housing today. It needs a little cleaning up and then I need to mount it to the truck before I can install my second heater unit. First though I need to get a air-filter for it. Does anyone know if "Wix" or "Donaldson" or anyone else for that matter makes a filter for this thing ? I don't want to have to spend a $100.00 for a air-filter ! That's the going price from the surplus stores right now. If worst comes to worst I'll just use one that is close to the proper size.

 

[skinnyR1]

View attachment 602081

The second picture shows my first heater mod.

I love this idea. Did you write about this previously? I need to change or fix my blown heater core, and would like to do this shortening mod while I am at it as well.

 

[turnkey]

great picks and idea...My dad installed a second heater system in a M35A2 he had...used a frod truck unit ...Not sure how he did it ....But it really did work great..great pics and idea...

 

[turnkey]

Sorry that was a Ford truck heat unit...

 

[rustystud]

I love this idea. Did you write about this previously? I need to change or fix my blown heater core, and would like to do this shortening mod while I am at it as well.

I posted my last one yes, but I got the idea from someone else originally.

 

[74M35A2]

rs, I don't mean to derail your thinking, but have you considered to place the heater inside the cab so it can recirc already warming air vs constantly try to increase cold air temp? WildChild467 did this on his M35A2, and we have to put his blower fan on low or even off, including when the temps are below 32F, and with his soft top on. He shortened his heater core box also, and then mounted it sideways under the center-pass portion of the dash. Retained diverter box, etc.... Did a really nice job, and it works amazing. Enough to get me to relocate the one on my 925A2 into the cab for the same purpose.

 

[rustystud]

rs, I don't mean to derail your thinking, but have you considered to place the heater inside the cab so it can recirc already warming air vs constantly try to increase cold air temp? WildChild467 did this on his M35A2, and we have to put his blower fan on low or even off, including when the temps are below 32F, and with his soft top on. He shortened his heater core box also, and then mounted it sideways under the center-pass portion of the dash. Retained diverter box, etc.... Did a really nice job, and it works amazing. Enough to get me to relocate the one on my 925A2 into the cab for the same purpose.

I had thought about it, but due to all the space needed I decided against it. How I plan to use my dual heaters is the original one will defrost the windows while the second will provide cab heat blowing at the floor. I found driving out here in the Northwest in the rainy season you need constant air flow on the windows or they fogged up constantly ! Actually the Northwest has only two seasons. A week of summer and then the rainy season ! It's just in Dec-Feb it's a cold rain !