Universal Under-dash heater

[investig8]

Greetings all,
I am looking to purchase a heater for my M37 and wonder if anyone has bought one of the universal under-dash heaters that can be found on Ebay. It seems pretty straight forward as far as installation but I am not familiar and was hoping someone might have some insight. Any info would be helpful.

[John Mc]

Is yours a 12 or 24 system?

A link to the heater you are thinking about might be helpful.

I have what I am told is a MUTT heater (but I have no idea), It takes heat from a coolant loop coming off the rear of the engine. It was on the truck when I got it. Seems like a nice fit, looks-wise for the truck. Installation appears to be fairly straightforward: run the coolant line to it, run the return back, hook up power and a switch.

Heater copy.jpg (124.99 KiB) Viewed 2143 times

Heater data plate sm.jpg (71.48 KiB) Viewed 2143 times

A friend who restores Dodge trucks uses a different type of heater. It's a smaller black box. I'll try to find the info when I go over to his shop today.

[just me]

I have a Maradyne Tucson skidsteer heater in my truck. Works well. Very loud fan.

[Cal_Gary]

John is correct-that's a MUTT heater. I also run it (below). 20,000 BTU, does fine unless you're in really bitter cold weather.
Gary

[John Mc]

Gary - Is that knob labeled "eng. heat" how you control it? If so, is that an electrical switch or a louver to cut off air flow?

My set up had no louver. Previous owner had converted to 12V, and just ran my fan off a 2-position pull switch. for high and low fan speed (which he left on high all the time, since running a 24V fan on 12 V was already slow). That switch failed, so I just temporarily replaced it with a toggle switch.

Since I'm converting back to 24V, I'm wondering if I'll want to regain some sort of adjustment on the heating beyond just on/off. I found that VPW sells the old style pull switch that was in there, but it says it's rated for 12V. Looking for good options for my control. I guess I could find a 3 position rotary or a SPDT center off toggle switch and wire in a resistor on one of the "on" positions, but thought I'd ask if you or someone had a better method.

Also interested to see if you have a defroster set up or not. I do not, but I haven;t been running much in the colder weather yet (I have the "Arctic Top", but almost no seals around my front and side windows at present, so there is a good breeze in the cabin. Once that gets sealed up, I may want to look at something to help keep the windshield clear. I may go with something simple and easily removable, even if it doesn't look "correct" and just take it out for non-winter use.

[investig8]

This unit is available on-line and seems very straight forward. Water circulated with a switch for 24v. Reasonably priced.

[John Mc]

This unit is available on-line and seems very straight forward. Water circulated with a switch for 24v. Reasonably priced.

Do you have a link or a name so we can search for it?

[m-37Bruce]

I too have the MUTT heater, Sam Wiener in Ohio must have bought everyone the Uncle Sam had, I think they still offer them? Cable Garbee's webpage has the complete install also.

[Cal_Gary]

@ John, that pull cable goes to a Ford-style manual heater control valve that I picked up years go, similar to this one:
https://www.amazon.com/HVAC-Heater-Cont ... 2555&psc=1

Pulling it opens the flow of coolant through the heater core. The little button next to the T pulls out to turn on the fan. They make the valve in 5/8 or 3/4 nipples depending on what you have (mine are 5/8).
Gary

[John Mc]

Sounds like a nice set-up, Gary. It would have been handy with the 230 engine I just took out of my truck: It had a much smaller hole than most where the temp sending unit usually mounts, so the previous owner mounted the sender in the fitting where the coolant hose for the heater connects. It worked fine as long as the coolant was flowing to the heater. However, the shut off was a valve under the hood (looked a bit like a garden hose spigot). For obvious reasons, it was left shut off in the summer. Every couple of days, I'd pop the hood and open the valve for a run to see how the temps were running. This type of valve would have saved a bit of hassle.

Maybe such a control is standard, but being the first antique truck I've owned, and the fact that this is a non-standard heater anyway, I just assumed that was the way these aftermarket heaters were set up. I didn't even think to look for a valve like what is in the link you posted. Something to add to my "to-do" list.

[John Mc]

Gary -
Do you have a source for the "Eng. Heat" knob? Or should I just check the "usual suspects" for something like that?

It looks like a good fit, visually with the rest of the dash.

[John Mc]

Getting back to Investig8's inquiry:
Vintage Power Wagon sells an under-dash heater. You can find it on the last page of the electrical section of their online catalog. It's available with either a 12 or 24V 3-speed motor. It's physically smaller than the MUTT heater. I think it also has a lower heat output as well, but not sure about that.

[investig8]

Thanks for the healthy conversation... The unit I posted the photo is manufactured in Italy. After the discussion, I'll pursue one of the recommendations... not so certain about the one I asked about.
Thanks again
Dennis

[Cal_Gary]

PM to you John.
Gary