M1010 A/C Compressor

[mkcoen]

After replacing the low pressure line and charging my A/C system I got air conditioning for about 15 minutes before the compressor locked up. I charged it with a product called DuraCool that is supposed to be R12 and R134a compatible and wonder if that might have been the cause.

Does anyone know of a drop in replacement A/C compressor for the M1010? Would the GM civi compressor fit the brackets? Since I have to change out the compressor what else would I need to do to convert to R134a?

Also, if anyone can read the model number on their unit I'd appreciate finding out what it is. The lettering on mine isn't legible.

 

[Warthog]

I'm think it was just time for the compressor.

From the -34p manual

compressor - 12300270 - item #10 figure 295
receiver/dehydrator (dryer) - 585810 - item #10 figure 299

Usually in civvy applications you would want to replace the orifice also but I don't see it in the diagrams/parts list.

Since you are changing out the compressor, you may want to convert to 134a. When you do this you can/should??? change out the o-rings and install the conversion adapters for the shrader valves.

 

[Recovry4x4]

If the refrigerant leaked out, so did some of the refrigerant oil. The by-product of the leaking refrigerant is that moisture can now "leak in". With that said, I think it's days (minutes) were numbered. My memory is poor but I think it's somewhat a run of the mill A6 compressor. As Warthog pointed out, replace that receiver/ dryer and it would be worth the effort to flush the system. Lavarok may have some input, he was able to get his A/C up and running on his M1010.

 

[mkcoen]

Thanks guys. I did PM Lavarok in hopes he could add some advice.

The reason for the leak was the ever present GL forklift. No telling how long the line was open. I was hoping since the unit had under 30k miles it would have held up a little longer.

I think at this point the repairs on the 1010 are coming to a halt. I would say it's nickle and diming to death but nothing has been that cheap.

 

[lavarok]

Mark,

Those AC compressors are supposed to be bullet proof...at least according to what the AC tech that converted my system to 134A told me. I think they can be repaired, where-as newer units are often a one shot deal. Using the part number supplied by Warthog, I found it crosses to "15-21680". I've seen them on Ebay as well.

My system had some leaky hoses, but I suspect age was the culprit. The worst thing for an AC system is for it to sit unused.

What were the symptoms of the compressor lockup?

Make sure the evap fans in the unit on the box are working when the system is trying to run. Otherwise your pressures will exceed nominally values and the system wont cool and might develop another leak.

To get my system working, I had to replace both evap fans, some hoses, a busted relay for the compressor, and then converted the system to R134A. I had a reputable local shop do most of the work and troubleshooting. I replaced the evap fans and relay myself.

To convert to 134A, they changed the oil in the compressor and some fittings.

Hope this helps.

 

[reloader64]

Mark, when I did my civvy vehicle, I was told that R-134A operates at a higher pressure than R-12. I recharged with R-12, and the compressor lasted about 3 days. I put a new compressor on (about $140.00) replace the filter, drier, and orifice, and had new hoses built. The theory on the hoses is that R-134A has smaller molecules, therefore it needs different hoses. I did all the work myself, and it worked like a charm. It will take more nickels, dimes, and dollars, though.

Scott

 

[M813rc]

Darn it, sorry you are having trouble with it still! In the long run, it is most likely worth it though, it is a very nice truck and you have put a lot of effort into it already.

On a selfish note - I was looking forward to a respite from the heat Sunday.

Cheers

 

[reloader64]

P.S. I would think the civilian compressor would work. I don't know why they would use a different one.

Scott

 

[acesneights1]

You have a CUCV with Air ? Does it have duals ? How is it mounted ? Any possiblity of pics ?

 

[acmunro]

It is an A-6 compressor. I have a 1982 K-10 with a 6.2 and it uses the same compressor.
On another note I just
replaced the A/C compressor on my 1990 V-3500 (ex Navy truck) (I think it is an HR-6 ?) with 6.2 and it was working great on my way to a
recovery yesterday, then I started hearing this unusual noise. The A/C clutch is coming apart. It was 465 air cond
for me again. 4 windows down drive 65 - Till the parts come to fix it.

 

[ken]

acmunro is right. It's a run of the mill A6 compressor. Used by GM since the 60's. Any auto parts store should be able to get you one.

 

[Warthog]

You have a CUCV with Air ? Does it have duals ? How is it mounted ? Any possiblity of pics ?

All CUCV M1010 Ambulances come with air. No pics but the diagrams are in the Tech Manuals.

 

[mkcoen]

Working off the part number that lavarok cross referenced I was able to find one at NAPA for $199 + core. Not too bad a price but the wife said "no." Instead we're spending Saturday afternoon shopping for a "reliable" (her words) vehicle since I have to have a/c due to the MS issues.

I'll piece things together over then next 6 months or so and hopefully have something going by next year. I hate doing this because currently we have NO car payments and I really don't want the debt but I also like being married so I'll cave on this one.

****

Forgot, NAPA part # in case anyone needs it is TEM251101

 

[Recovry4x4]

acmuro, nice to find a V-3500 Navy truck with a/c.

 

[acmunro]

acmuro, nice to find a V-3500 Navy truck with a/c.

It is a pretty good truck. I picked it up at Fort Jackson SC last year. The negative on it is it has 4.56:1 gears and a TH400. The other day I picked up a
1991 V-3500 (ex-Navy) I just got it running this afternoon. I took it for a little ride down the road to try it out. That 4L80e is great. The negaitve is it does not have AC. I do have a 1990 Suburban I will prob transfer the AC from it.

 

[mkcoen]

Well I got the new compressor in, hooked up and putting out about 52 degrees at the vents. Everything seemed to be going well and with an AC invertor and box fan in the ambulance body took the 1010 to Ft Sill to pick up a 1009.

When I got up to check the belts and fluids yesterday morning I noticed the compressor clutch was HOT (9 hours after it ran last). I'm guessing it was drawing a charge somehow so simply pulled the plug off the compressor.

Any ideas what might be causing this?

 

[lavarok]

> NSN: 5945-01-166-2012
> Part Number: 19-0876
> Description: RELAY SUBASSEMBLY
> Manufacturer: MARK BODY TRUCK AND EQUIPMENT INC

Part number 8 in the attached diagrams. I just submitted a RFQ through parts logistics for the item. If I get any hits, I'll PM you.

 

[lavarok]

By the way, I had this information readily available as the same relay was bad in my truck. It controls the compressor clutch and when bad allows the clutch to always be engaged.

 

[mkcoen]

Where's the sub assy located on the truck?

And which one runs the clutch for the compressor?

 

[lavarok]

Under the bench on the drivers side, above the wheel well.

Part #8 in the diagram is what you need to check out.