Heater Upgrades for '74?

So, I've searched and read about upgrading heaters, but most threads are either related to the early style heaters, pre '72, or '78 and later heaters. Not much info out there for the '72-'77.

I've got the heater assembly out of the Jeep right now while the body is off. Before I put it all back in, are there any upgrades I should consider doing? The old defroster plenum is shot, but the PO had already purchased the aftermarket plastic ones as replacements. Now, these only have one inlet, so I imagine I will have to block the other outlet from the heater box.

How about the motor? Are there any aftermarket replacements that will improve the amount of air being moved? The "blazer motor upgrade" seems to pertain to the later model heaters, so I don't know if that's even an option. I've also heard the aftermarket stock replacement heaters are only one speed.

My current system worked when I pulled it, but not efficiently. I am happy to put it all back in as is, but while it's out, now is the time to spruce it up if at all possible.

Or should I chuck it all and install a Heatercraft style aftermarket heater? If I went this route, I would lose the ability to draw outside air, correct?

Thanks!

 

I don't know of any specific upgrades for the intermediate Jeeps. It's likely that you could come up with a motor upgrade, similar to the one for later Jeeps, if you do a little research and are handy with small-scale fabrication.

The extra defroster inlet is taped up from the factory. Some people have found a plastic cap that fits over it, for a little tidier seal.

My guess is that loss of performance from the heater comes from the housing getting leaky and the heater core getting blocked up. You could replace the heater core and gain some heat that way. Sometimes the heater gets filled with debris. You need to run the right thermostat too.

 

I have heard that the back seat heaters will run you out of your Jeep when they are running. It is very simple to hook up as it wires up 12 volt. Now I don't know if your trying to keep it original or your trying to keep it warm.




Todd

 

i installed a blower motor from a mid 80s dodge ram , its bit bigger than the stock motor, ,not too sure if it blows more air becouse my stock motor was TRASHED.

 

The original heaters were called whisp heaters because you got a whisp of air out of them.






Todd

 

I installed a new heater core and new stock fan for my 73 and it blows well. The only thing is the stock one is either on of off, no middle. The motor I took off had three wires, maybe for a different year. The new one only has 2 wires.

 

Add one of the old rear heaters out of the toyota land cruisers.

 

Why don't you just get one of those Summit (mojave stlye) heaters, there like a hundo and would probably melt your legs, that's what I'm going to do just for the simple fact that I have a birds nest of wires and garbage under the dash and don't want to mess with it...

 

Thanks everyone for all the responses! As I mentioned, the system worked when I pulled it out. I was just wondering if there are things I should do while I have access. As with most things regarding the Intermediate Jeeps, it looks like I don't have much of a choice, as there is no proven "recipe" like the later models have.

I have also considered the aftermarket heaters, having read good things about them. Based on what I see in the pictures of them, it would seem that I would lose the ability to draw outside air. Probably not much of an issue in a leaky Jeep, but what do I do with the cowl vent? Block it off? All things to consider.....

 

the plastic cap from a pint of DuPont hardener fits the extra defroster hole perfect....