How to plumb and auxiliary heater in my M1009

[acesneights1]

Tired of freezing my nuts off in this frigid weather. I have a universal 12v auxiliary heater similar to what the civvy suburbans had. Should I t each coolant line or hook the auxiliary heater in series with the cab heater ? Also which hose if I do the cab heater interrupt ? Upper or lower on the cab core ??

 

[cucvrus]

When we built Air Force expeditor trucks we just put Y's in the heater hoses. Both have shut off valves built into them. They were 12 ft bodies and had a heater on the rear floor. It does help to put a small pump in to help circulate the water. Either way heat will push its way thru after you get the air purged out of the system. Also adding the artic front will do wonders. I drove my M1009 to Ft Drum over the weekend and it never went above 130. I put a piece of cardboard over the grille on the way home and it was night and day. Actually got hot on the way home and it was dark.

 

[acesneights1]

I have cardboard in front of mine. Still freezing..
Even put a brand new GM T stat. Problem is it is so cold here that the fresh air coming in is cooling the core off too much.

 

[doghead]

Maybe your core is plugged.

Have you flushed your coolant system lately?

 

[NEWFDAD]

I've driven my M1009 in -20F with the grille blocked and have good heat output! I agree with doghead, check your core.

 

[acesneights1]

Maybe your core is plugged.

Have you flushed your coolant system lately?

yes. When I bought it I found the t stat incorrect installed. I drained the system, flushed and refilled. Both my Cucv's are falling short and the one has a new core(brass) in it. It is very cold here. When the temps go up to the 20's it's not bad but the last few below zero mornings have been a little rough.

 

[Skinny]

My M1031 has always kept me in a t-shirt in the coldest weather. If anything I've found that air leaks from the firewall, fender vent, and trans tunnel to be the worst culprits.

I double a radiator shield, old 6.2 struggles to come up to temp on the really cold days. As far as an aux heater, probably not needed but the engine should be making enough heat to run two cores in series. I could burn my hand on the return line without question at operating temp and heat on full blast.

 

[pbrstreetgang]

im having the same trouble here.

I have replaced my core with a good copper one, and I have sealed my box really good with duct tape and sealant / spray paint around seams and any small cracks. New t-stat, New Rad Cap, topped off fluids, all good. T-stat opened in water on the stove, so it works.

I have checked my blend door and my vents and they are fine.

Where else is air supposed to come into the cab? Is there an outside air blend door, or maybe the vents in front of the windshield?

I used to be able to bake cakes in the truck, but now can't defrost my windshield. The heater hoses are real hot.

I am tired of seeing my kids freeze on the way to school in the mornings. I either find a fix here, or rip out the GM box and put in a summit racing heater kit.

 

[cucvrus]

Do you have the firewall insulation inside of the cab on the firewall yet? That can cause an issue if it is missing. I have mine removed on my Mule and had to change the fasteners so that the heater box was tight against the fire wall under the dash. That little gap makes a world of difference. Also head gaskets can cause it to not make heat. That is an extreme case, but I have had that happen already. Check you seals at the heater box. And check your heater motor. At this point in time the squirrel cage fan is disintegrating from age. A few missing blades on the fan cage will cost you heat and circulation. Also Mr. Rat face / Mouse face finds the heater box area the perfect home. Check it out.

 

[Hasdrubal]

Also Mr. Rat face / Mouse face finds the heater box area the perfect home.

In addition to having to throw my rear seat out as it was full of turds. The heater box had turds dropping out when I hit it with a vacuum. Took it apart, there was a mouse nest in it with a dead mouse jammed in the blend door.

 

[cucvrus]

You just can't not make this stuff up. It really happens. Mud wasps have brought down 747 jumbo jets. It is amazing what you will find living inside and under vehicles. Snakes , Possums , Skunks , Rats/Mice , Squirrels , Cats , Groundhogs , Dogs , Bats , Bees of every shape and kind just to mention a few of the lovelys I found in vehicles over the years. Even a homeless couple were living in the back of a box truck I hauled in. They went for a ride. I never knew they were there. Hooked it up locked / latched the back door and took off. They were scared and afraid. I was more scared when i opened the back door after hearing the screaming and yelling. It is always advised to remove the heater box and disassemble it and clean it well. Also clean and inspect the air box and blower motor under the hood. And they do love living in the defrost vents or they just use that to pack there trash in there and use it as a bathroom. Have fun.

 

[dstang97]

You just cat not make this stuff up. It really happens. Mud wasps have brought down 747 jumbo jets. It is amazing what you will find living inside and under vehicles. Snakes , Possums , Skunks , Rats/Mice , Squirrels , Cats , Groundhogs , Dogs , Bats , Bees of every shape and kind just to mention a few of the lovelys I found in vehicles over the years. Even a homeless couple were living in the back of a box truck I hauled in. They went for a ride. I never knew they were there. Hooked it up locked / latched the back door and took off. They were scared and afraid. I was more scared when i opened the back door after hearing the screaming and yelling. It is always advised to remove the heater box and disassemble it and clean it well. Also clean and inspect the air box and blower motor under the hood. And they do love living in the defrost vents or they just use that to pack there trash in there and use it as a bathroom. Have fun.

thats a pretty funny story

 

[nyoffroad]

. Even a homeless couple were living in the back of a box truck I hauled in. They went for a ride. I never knew they were there. Hooked it up locked / latched the back door and took off. They were scared and afraid. I was more scared when i opened the back door after hearing the screaming and yelling.

That could've gotten real interesting if a cop had've stopped you!