Heater sucks... Supposed to blow?

[merlot566jka]

Ive got an interesting heater....

Looking at all of the pics of everyone else's heaters, it looks like mine is completely different. Its mounted in the cab and doesnt have the same style of blower. The blower draws the air from the heater core and the outlet is facing straight up. There is some home made ducting going to the defrosters. there is no outlet for the cab.
On the bottom of the heater the data plate reads nsn 2540008690424, 20,000 btu, HW-20-2, 6a, 28v

I have replaced the motor with a 24v siemens unit from napa last winter. It never dawned on me to see if it was the right kind of heater. It doesnt look like anything else I've seen in pictures.

 

[merlot566jka]

update...I think its an m151 heater???

 

[197thhhc]

The m151 heater box is a good upgrade. We use them on the trucks we restore. It puts the heater core in the cab and works pretty well. You have to custom make your ductwork. Does yours have a blower issue or just a routing problem. If its just a routing issue they arent hard to fix and I think the heat works better than the underhood unit

 

[merlot566jka]

Upgrade? really?

The m151 is so small... I thought the deuce heater was a 30,000 btu... bigger than the m151's unit...

 

[AceHigh]

I put a 151 unit into my deuce and it is great but... If I let the antifreeze drop a little it goes cold. Have to keep it up a little in the neck of the radiator.

 

[197thhhc]

The deuce unit is 30k btu m151 is 20k btu. I think you lose the extra 10k pumping the air through the underhood ductwork to the cab. We took the under hood unit off our test truck last winter and installed the underdash unit( M151) and we were amazed at the difference. It will run you out of the truck. If you pull the box apart on the underhood unit you will see how tiny the heater core is. Plus it makes the engine compartment look better.

 

[rneely]

 

[runk]

The M35A3's have the heater box under the dash (passenger side) as well. Same parts as the A2 under hood units, I think (haven't actually compared the part numbers from the TMs). The cab/defroster diverter is flipped around with the mounts re-welded on what would be the front in the A2 application.

 

[AceHigh]

The A3 heater is a Hunter HW30, 33,000 BTU/HR, 6 amp.

 

[AceHigh]

TNJMurray has the A3 heater, but it is not cheap.

HEATER KIT HOT WATER M35A3 | M35,M35A2 | Military Vehicles For Sale | Military Trucks For Sale | M35 A2 | 5 Ton | M151 A1 A2 | Surplus Parts - TNJ Murray

 

[sandcobra164]

TNJ has $9.00 battery terminals that you can get for $2.00 at NAPA, possibly same part number. Don't get too wrapped up in that, just know you can find a heater kit NOS for well under half.