FMTV Air Conditioner Hybrid Completed Installation

Nice write-up and fabrication. Assuming an A1 truck with the serpentine belts... Weird coincidence, I just got a hold of a bunch of A1 A/C compressor double belt crank pulleys that would allow this setup to work with the stock compressor brackets over on the driver side. Only works on the A1 engine though so I can't use them on my A0 truck but will be selling them shortly.

OD

Anyone near Wauchula, Fl with a M1078 A0 / 3116 engine that would like to do this type of AC installation and has the main components? I would be willing to prototype and build the kit and only charge you for what it cost me to make the parts. I would also HELP install it for free. Although, you would need to be close enough that you would be able to commute back and forth to help with the installation. I would also need your vehicle for at least a couple of weeks. Email me at keith@innovativemachineworx.com

Kambaku said:

You can see from this image what I am referring to if you compare it to the posted image on the thread. The brackets are different. This is my new fan unit and nice clean condenser.

View attachment 622572

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Kambaku, did you just drill into the frame rail to mount the L to the truck or is there a bracket in there? All the stock condenser/fan units I have come with those L brackets.

Also have an alternate condenser like Keith has that fits pretty sweet behind the cab right over the hydro unit and still lets you service the pump. Have to fab up a bracket to mount it though. I will be working on setups for both stock and alternate condensers.

Thanks!

OD

The A/C was installed in the truck when I got it. So all I did was a bit of maintenance. She's working fine now.

ok... looks like they are just drilled into the frame rails with no additional brackets used other than the L's on the condenser.

There is actually another bracket on the end of the frame rails. It is difficult if not impossible to photograph this without pulling off the big front plate. So those small "L" brackets actually attach to a much larger bracket that in turn attaches to the frame rails. Regardless, it would not be too difficult with a little imagination to fabricate attachments for the condenser if you wanted it mounted in a similar position.

oh come on Kambaku, just unbolt the skid and take some pics for a pal

I may mess with this soon to see about getting one of the stock condensers I have installed there.

Oh that hurts because I know you would come to my aid. Truck not here, but I will crawl under it over the weekend and see if there is anything worth photographing without some surgery.

You are the man! Of course I am always willing to help no worries if you can't get to it.

Does any one have condenser mounting brackets & an air conditioner drier? It's the last 2 things I need (other than hoses)

Rage said:

Does any one have condenser mounting brackets & an air conditioner drier? It's the last 2 things I need (other than hoses)

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I have not been able to find the brackets anywhere. I'm just going to fab something out of angle iron. Hopefully the splash plate will cover it up so no one will be able to tell it's not original.

After seeing and talking with others on this site about their AC cooling performance not being what we expected and with very similar results on out put temperatures.
There are only a few main components to an AC system such as the Compressor, condenser, drier, evaporator, and the expansion valve.
I'm unwilling to give up the thought of achieving 40 degree air coming out off the vent first thing in the morning before any heat of the day plays a part.
So my question is, If I was a AC engineer and wanted an AC system to produce colder results what component would I look at changing first and why?

Rage said:

Does any one have condenser mounting brackets & an air conditioner drier? It's the last 2 things I need (other than hoses)

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I've got the drier. The condenser brackets are made from unobtainium.

Keith Knight said:

After seeing and talking with others on this site about their AC cooling performance not being what we expected and with very similar results on out put temperatures.
There are only a few main components to an AC system such as the Compressor, condenser, drier, evaporator, and the expansion valve.
I'm unwilling to give up the thought of achieving 40 degree air coming out off the vent first thing in the morning before any heat of the day plays a part.
So my question is, If I was a AC engineer and wanted an AC system to produce colder results what component would I look at changing first and why?

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The best A/C systems can only lower the intake air across the evaporator 25-30 degrees and this is generally for very dry air. Add high humidity you loose some temperature differential to take water out of the air. Your not going to see 40 degree vent temps with the cab at 85 degrees and 100+% humidity on startup, you have to dry the air in the cab, and then cool it. You won't see 40 degree vent temps until the intake temps reach 70ish.. And the LMTV cab is for all purposes insulated. The best bang for the buck would be to insulate and seal up the cab.

The factory LMTV condenser sucks. It's one of the least efficient in construction (tube and fin), and it's also mounted in a poor location. The shrouding is horrible.

The system in general is undersized for the volume of the cab, add in a windshield the size of a football field and that allows alot of heat to enter from sunlight.

I'm sorry but I believe it is possible! If you look at my installation you will see I'm not using the factory condenser and it's located in a different location. Also I'm comparing it to my 2003 Cherokee parked right next to it, in the morning before the sun comes up and the Cherokee will put out 40 degree temperatures every time while the red dot system struggles at 60. Even spraying the condenser with water it won't achieve 40.
So what would be the next thing to change and why?

Keith Knight said:

So my question is, If I was a AC engineer and wanted an AC system to produce colder results what component would I look at changing first and why?

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Change the evaporator to the 2G version with the 4 vents. The 1G is a leftover design from the HIMARS and it would appear S&S knew it was not cutting it and had Red Dot come up with the new larger evaporator.

Very good information thank you.

One step closer. While trouble shooting the AC this morning before the sun was up, I wanted to verify the thermostat was working properly. The thermostat is factory set at, off at 31 degrees on at 39 degrees. With the volt meter monitoring the voltage coming out of the thermostat so I could see when it is cycling the clutch. I used an IR temp gun to get temperature readings from the evaporator. Heres what I found.

The cooling fins marked with green were reading 82 degrees from top to bottom and the rest of the fins were reading around 60 degrees. So the compressor never had a chance to cycle.
I'll give Red Dot a call today about that.
Also the Evaporator measures 10" wide x 9" tall x 3" deep.
Does anyone have the evaporator dimensions for the GEN2 units evaporator?

deleted the duplicate post.

The second gen was designed for the Caiman.