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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #1 (Edited)
This will be an ongoing thread as I finish the details of the system which tie into a few other projects which are not complete.

This install required me to remove the Factory Unimog heater box but my VA unit has its own heater.

The mounting of the evap unit under the dash does not interfere with passenger foot room at all.

Truck: 1985 U1300L
AC: Vintage Air Compac GENII with defrost
Compressor: VA Sanden 508
Condensor: VA superflow vertical
Main fan: Volvo 740 Electric fan 2 speed through rad and cond
Aux fan: Hayden 800CFM 12" 255PSI trigger
Fan trigger: VA trinary switch
AC control: Arduino bluetooth connected to Ipad or similar
Hoses: VA std hose kit with parker dryer + 3ft of extra low pressure line and a few fitings
Comp Mount: Custom

So I needed A/c for far to many reasons to list. After lots of internal debate about how I will use my truck, I decided that an internal system (under dash) was critical as I cannot deal with being any taller and an external system (roof mount) would be quickly damaged. Plus I have a military version with a turret hatch that I wanted to maintain just incase I decide to mount up a 50cal:D

After considering building my own evap box etc, I decided the best setup for the moment was to buy an existing unit. Vintage air seemed to fit my needs best and I felt it to have a better rep than some of the other off brand units.

Rented a mock up unit from a local shop and verified fitment. After fitting the mock up I felt comfortable with going whole hog. Fitting the evap box requires minor trimming of the lower dash support and deleting the glovebox which was full of crap anyhow! The unit really fits like a glove (pardon the pun). The one downside of mounting the unit in this location is that you cannot easily run the floor mode over to the driver side. I will address this later on I suppose but at least the complaint department has cool feet in the meantime. Getting a vent ducted tot he driver side of the dash was fun, but I managed to snake a 2" duct all the way just above my headlight switch.

The condenser was by far the easiest part. Because I was already running the volvo electric fan I was able to rake the top of the rad back a bit more by adjusting my top mount strut. Then I did some minor trimming to the lower grill rad mud guard. Once I had everything clear, I used some 3/16" X1" steel falt bar to span the radiator front flanges and riveted the condenser to these straps. This left the condenser very secure with just enough give to the mounts for some isolation. The parker receiver dryer came with a pair of simple brackets that allowed easy mounting where the old mech fan pulley system used to sit. Simply bolted the dryer to the rad flange.

The compressor was the hardest to mount I guess if you want to call it hard. I decided to do a lower mount to keep the topside of my engine more accessible since you have to use a ladder already for any maint. I attempted to make the bracket as close to what I feel merc would have done if they went this route. Right now of course the bracket is fabricated from tubing and flat bar, but I "might" have it machined out of a billet at a later date just for some bling. I really just needed the dimensions and the first mockup bracket fits perfect. Basically it functions the same as the power steering pump allowing you to adjust the belt tension with a vertical bolt coming down from the engine front mount. Hopefully the pics explain it better.

Hosing the unit was fairly easy. I still need to clean up the heater core hose setup, but it works for now. Basically I just need to buy a proper bulkhead fitting for this. The A/C hoses were fairly straight forward. I did have to substitute a few of the standard VA fittings to mount everything the way I wanted and to give access to the charge fittings. Having a local shop (45min) with all the parts on hand made it fairly easy. And since the hose kit is not crimped so you can fit it to your application, all you have to do is fit and mark your hoses for the VA shop to crimp them for free.

The electrical is largely what's not "complete" the VA system is very easy to wire and get running. But I have been beating myself up about the control unit and my new dash layout. I actually removed the stock face plate from the Unimog heater box and partially converted it to operate the VA unit, but I just didn't like it and have not completed it. My original intention was to install a decent in dash radio and use the Dakota digital VA control unit. But I found myself not liking that setup for some unknown reason. At the moment I am attempting to use an Arduino open source micro controller to operate the ac. The Arduino will receive bluetooth or wifi signals from an Ipad or Iphone mounted on the dash front and center where the heater unit used to sit. I may also program it for a proximity ignition. Just letting a bit of my Geekyness out to play. I ended up upgrading my 24V to 12V system from the one in the pics to a couple of PWM units capable of putting out 50-60 amps. One runs the A/C and the other runs my electric engine fans. This allows for redundancy if I loose the engine fan unit I can easily rewire the A/C power supply to run the engine fan in a pinch..

Anyways, hope This explains most of it. I will add photos of the completed dash once I decide how I am finishing it etc.

As for performance. Well she blows cold ass air thats for sure. I have read temps as low as 28*F at night coming from the center vent with fan on intermediate. Day time is a bit more of a struggle though. I am finding that insulating my cab is going to be very important. The unit most certainly keeps you below the sweat threshold on 100*F days, but I really want ice hanging from my chin. I have found that the massive amounts of bare hot steel in the cab really need to be tamed to do this. I am guessing this will be a long work in progress as I want to do it all "right" and update/civilianize the cab interior. I will of course add as much of this work to the thread as I go.

Now for pics.

 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #2
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All I had was high gloss spray paint for the comp bracket. Makes it hard to see a bit.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #4
Cool! (pun intended, groan).

The compressor looks to be about where my hydraulic pump is, if I remember correctly.
Yep, it's a factory location for another hydro pump. I had an alternate location but this was the easiest by far. Of course it won't work for everyone.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #6
The idea will be to put a ram ball mount dead center where the old heater controls were. Then an IPad docking mount or similar from Ram. I will also use the iPad for music as well.
 

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Unimog U1250
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Please can you send some more photos of how you compressor mount works - a few from above looking down onto the pump from directly below.

Which belt do you run off , do you keep the OEM bracket for the hydraulic pump which is part of the engine mount, and if so, what connects to what.

I want to mount my auxiliary air compressor (Endless Air- modified a/c compressor) in the same spot - just figuring out how to do it as we speak.

:bowdown::bowdown::bowdown:
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #8
I will try to get better pics today.

I did use the built in factory hydro bracket on the right side of the truck. I used the furthest forward crank pulley.
 

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U1300L Turbo x 3
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It looks like a well fitting install with that VA unit. So I am assuming it's got a heater core as well as an evaporator, right?

One thing I really liked on the greentop kit was the dash knee pad thing. At the very end of the new dash pad was a vent you could blow cold air right up your shorts to keep the sweatynutz under control. ;)

It would be pretty easy to build a similar device - probably just some long strips of ABS plastic and cement them toether to form a very long triangular shape, which becomes the duct. Then, hole saw some vent holes in the knee pad.

I'm guessing that you're being hampered by the lack of outlets for air more so than the unit not keeping up.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #11
It looks like a well fitting install with that VA unit. So I am assuming it's got a heater core as well as an evaporator, right?

One thing I really liked on the greentop kit was the dash knee pad thing. At the very end of the new dash pad was a vent you could blow cold air right up your shorts to keep the sweatynutz under control. ;)

It would be pretty easy to build a similar device - probably just some long strips of ABS plastic and cement them toether to form a very long triangular shape, which becomes the duct. Then, hole saw some vent holes in the knee pad.

I'm guessing that you're being hampered by the lack of outlets for air more so than the unit not keeping up.
The heater core and evap are all in the same unit. As for crotch air, it would be easy and is just a matter of vents and hoses.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Unimog U1250
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Thanks - I'll be doing something very similar now - I have to use a different belt as I use the front two for the a/c and alternator, the rear most one for the waterpump & alternator, and the second one for the power steering (IIRC) - that leaves two more for the air compressor. I think you design will work great.

Thanks again
 

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1984 schmidt u1700
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hi kc,

what was your alternate location? i've got a pump in that location and would like ac at some point. i was eyeballing the rear pto, but don't know if there are reasons why that is a bad idea.

thanks,

clay



Yep, it's a factory location for another hydro pump. I had an alternate location but this was the easiest by far. Of course it won't work for everyone.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #15
My alternate location involves a little more work. Basically I was going to stack two sanden 7series pumps and remove the factory air system compressor and mount the sandens in its place. One sanden would run the ac and the other would supply the Mogs air system.

This is potentially a good upgrade due to the fact that the sanden has a significantly higher CFM and should renew your system faster than the stock pump. I planned on using the oil system configuration from the old mog compressor to oil the sanden. You will also be able to electronically control your air system as well as use the factory mechanical pressure relief. This will help while driving down the highway when your not using your brakes all the time. Also, you will have an easily replaceable pump in case you have an air system pump failure. The mod required to actively oil the sanden is very easy to perform even in remote locations.
 

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Unimog U1250
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Any more details on the active oil system, the Sanden based air compressor I have runs with grease - and needs greasing every 10hrs of running time - I have an hour meter for it to enable me to check, but since I have the OEM engine block mounted one as well, it will mainly be used at start-up and for air tools/tyres etc. Love to make it run on oil and recirculate it instead of trying to figure out a catch can for the grease. Running the two in parallel has some interesting modes when the engine one runs, the other is stopped. In the circuit is a check valve, pressure relief valve and a pressure sensor to shut the auxiliary compressor down before the relief valve opens.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #17
There are a few write ups around. I will look for a link, but basically it goes like this.

The best I recall is as follows
The sanden is meant to run on oil to begin with. However it has a port that moves oil from either side of the pump. This port must be sealed/plugged to keep oil from flowing from one side to another. Once you plug this, you can fill the pump up with the prescribed amount of oil and it will work just like the grease conversion. But you will have to refill over time. But you can add a banjo to the fill port on the sanden and drill a drain hole roughly perpendicular on the side of the case to allow oil to drain out of the pump at the correct level. Now you have a recirculating and cooling oil supply. Yes it requires disassembly of the pump, but they are relatively simple once you get it open.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Discussion Starter #18
Still have to add some spacers to line up the dash panels and the radio fires up but is just for show at the moment. Still need to add speakers. Otherwise its coming along. Lots of details to clean up and driving it all the time makes it hard to put her down while I knock all the punch items out.
 

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250GD Wolf
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Photo was too low a resolution to do much with, but it was way to dark for my eyes. Plus, Land rover. Fixed? :p

Edit, ok, first one is much to grainy, had to leave the LR in this edit :D

I could barely see the gizmo under the deck before. Is that the HVAC control?
 

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