M818 heater help needed

[818 Test Pilot]

just bought a 1979 M35A2 24 volt heater. Hopefully one way or another this will fit in my 1971 M818. If you have seen one of these give me a couple suggestions as to where it goes. OIF1 88M

 

[simp5782]

Where ever you want it to go that makes you comfortable. My heater was a cooker so I took it ou

 

[NovacaineFix]

Looks like you're missing a few parts, or they are just not in the pics. Either way, I have the same issue on my 818. The heater was deleted or cannibalized, who knows, it was not there when I bought it.

Here are the diagrams for the install. The heater core box mounts just below the the surge tank and above the muffler, you may be missing some mounting brackets as well.

The heater control box or plenum mounts center below the dash in front of the shifter, there should be 4 holes in the firewall in a square formation.

 

[jasonjc]

Most trucks did not have a heater at all. That one looks more like the one for the arctic kit , not the everyday heater like is show in the above diagrams. It mounts under the glove box on the deuce not 100% on the 5 ton but would guess the same place.

 

[818 Test Pilot]

Simp5872: thanx for responding. during training up north prior to OIF1 two types of 818's and some 931's were parked in the lot during a pleasant winter day. the gate opened and choose your rig. Little did i or most knew 1/2 the 818's were heaterless. I by mistake picked a pretty green 818 with a heater that kinda didn't make a difference in 20 below and more training. So even if my newly bought heater was just bolted somewhere without anything hooked up I would be happy. OIF1 88m

 

[818 Test Pilot]

818 heater

novecanefix:
the previous parts owner said it goes under the passenger dash area. Yup got the control box and do see the 4 holes all set there. Bought some duct hose at parts store and the other guy in this post area said its a winter kit which i believe cause most i see online the heater box is displayed on right and left of engine.

 

[818 Test Pilot]

jasonjc: yup i did have the chance to wait and get the the heater in above diagrams but i didn't. Thanx for the hint its in the arctic kit. I like seeing there is existing holes covered over from the factory been sitting there doing nothing but i know something might mount there somehow. My guess is the arctic heater kit calls for new holes. thanx

 

[NovacaineFix]

You're probably right on the mounting if it is an arctic heater kit, the ones I showed are just called Personnel Hot Water Heater. They had several different types, 2 were diesel fired heaters, one that mounted under the hood and the other was mounted in the front battery tray.

As long as it fits and works, it really doesn't matter, you just don't want to create more work if there are already holes for mounting and hose routing.

Mine looks much different than yours, as mine is the personnel heater type, it's not yet complete, missing the blower motor, duct work and the heater diverter box.



Good Luck and keep us updated.

 

[818 Test Pilot]

You're probably right on the mounting if it is an arctic heater kit, the ones I showed are just called Personnel Hot Water Heater. They had several different types, 2 were diesel fired heaters, one that mounted under the hood and the other was mounted in the front battery tray.

As long as it fits and works, it really doesn't matter, you just don't want to create more work if there are already holes for mounting and hose routing.

Mine looks much different than yours, as mine is the personnel heater type, it's not yet complete, missing the blower motor, duct work and the heater diverter box.

View attachment 649912

Good Luck and keep us updated.

10/4 on the update

 

[country]

The diverter box on m809 is different than m35 and other 5 tons

We have used diverter boxes for $25 we also have new old stock m809 heater kits in stock

dave
www.easternsurplus.net

 

[818 Test Pilot]

The diverter box on m809 is different than m35 and other 5 tons

We have used diverter boxes for $25 we also have new old stock m809 heater kits in stock

dave
www.easternsurplus.net

heres the heater and diverter box. guessn its not a match? there is two separate 24 dc blower motors, one with a fan directly behind the heater radiator in pix. a few louvers can open on the housing box to heat cabin. the two 2" heater duct hose attach to the external 24 dc motor outputs shown and attach to diverter inputs. i guess. but how does hot air get to windscreen defrosters from diverter? just wish there is an mwo# or parts diagram of this special heater i have.

 

[country]

your diverter box is for and M35/M54- as you can see the input is fed from the driver side of the cab when mounted under the dash. the defroster connections point upward

see below, not certain why the diverter box is not in the picture

Dave
www.easternsurplus.net

5T-672 | M809 Series Hot Water Cab Heater Kit
Hot water cab heater kit with all brackets to mount the heater and ducting for floor heat in the cab of the truck. Fits M809, M813, M814, M816, M817, M818 5-Ton Trucks
NSN #: 2540-00-168-9974
Part #: 11648557
Price: $675.00

 

[818 Test Pilot]

your diverter box is for and M35/M54- as you can see the input is fed from the driver side of the cab when mounted under the dash. the defroster connections point upward

see below, not certain why the diverter box is not in the picture

Dave
www.easternsurplus.net

5T-672 | M809 Series Hot Water Cab Heater Kit
Hot water cab heater kit with all brackets to mount the heater and ducting for floor heat in the cab of the truck. Fits M809, M813, M814, M816, M817, M818 5-Ton Trucks
NSN #: 2540-00-168-9974
Part #: 11648557
Price: $675.00

well committed to the heater i have. if i had to do it all over again would purchase your heater kit for sure. just a note, the metal heater box i have has a few open/close louvers to heat passenger floor area. the big 24 vdc fan in pix is the one that draws heat of the radiator. there is no actual diverter feed hose connection on this heater box assy. the small windmill 24 vdc motor has two connections on it for the two windscreen defroster hoses. found a mounting area on floor under dash. I think

 

[818 Test Pilot]

your diverter box is for and M35/M54- as you can see the input is fed from the driver side of the cab when mounted under the dash. the defroster connections point upward

see below, not certain why the diverter box is not in the picture

Dave
www.easternsurplus.net

5T-672 | M809 Series Hot Water Cab Heater Kit
Hot water cab heater kit with all brackets to mount the heater and ducting for floor heat in the cab of the truck. Fits M809, M813, M814, M816, M817, M818 5-Ton Trucks
NSN #: 2540-00-168-9974
Part #: 11648557
Price: $675.00

you don't know how close i was to to a sale with your quote on a universal type engine compartment assy. but.... fixed my unfriendly heater core assembled everything, balanced and black painted and now have to fire up the mig and produce an internal mount under dash area i guess. just wish somebody could produce a installed heater picture like mine in picture installed correctly on whatever this model heater was designed for. yup

 

[NovacaineFix]

You sound like me at times. When it doesn't fit, make it fit, with a welder, grinder a little fab work and some creativity, and maybe a few beers to help calm your nerves (or soda if you don't drink)