The son's 90 model has some kind of after-the-fact air-conditioning.

It appears to be all there and the belt is routed around the compressor.

The hoses enter through the firewall on the driver side, between the steering column and engine, instead of through that rubber X, on the far right side, like the wife's does.

The bottom heat control lever has A/C on extreme left, HEAT in center, and DEFROST at extreme right.

At the right end of the levers is a fan-speed switch, with OFF-1-2-3-4 (not really sure about -4-, it may only have -3-).

I have not, as yet, figured out how to turn on this A/C system, nor can I get any blower action at all.

I have no idea what brand this system is.

Does this sound like anything anyone is familiar with??

Any in-put would be appreciated.

Thanks.

 

Doesn't sound like dealer installed a/c to me. I've installed lots of the Mopar kits (on 2nd gen trucks. Never done a 1st gen.) and when it's installed, it's not possible to tell that the vehicle didn't come from the factory with a/c. Every part was the exact correct OEM part for the vehicle. What you're describing sounds like a generic aftermarket a/c kit installed by an a/c shop. Don't have a clue about the brand though.

 

i was looking a peyton's truck at the kentucky event and i believe he has dealer added a/c. everything looks factory exept the mopar accessory label for the charge on the radiator support. really clean factory looking conversion. yours sounds to be an aftermarket add-on. there should be a tag or sticker somewhere under the hood with the name brand of the kit and the amount of charge. these things can be really hard to locate parts for.

daryl

 

There should be a separate button to turn on the A/C. As for the blower, it sounds like the relay is bad. That maybe built into the heater controls in the dash.

 

Read this, as it goes along with the A/C question.

https://www.dieseltruckresource.com/...d.php?t=155657

I have not seen any tag/sticker anywhere, that has anything to say about the A/C.

It is now blowing decently COLD air.

The blower-fan speed switch has four speeds, each speed requiring some judicious switch-wiggling to make contact and kick on.

There is a top lever that travels horizontally, with COLD on the left and HOT on the right; I imagine it moves a cable that operates a door, somewhere in the ductwork.

Below this lever is an identicle lever that has A/C on the left, HEAT in the center, and DEF on the right.

Placing the top lever on COLD, the bottom lever on A/C, and selecting any fan-speed position except OFF, will turn on the A/C.

Now, if I could just find out what kind of refrigerant it has and find the fill/check port that the gauge gets screwed on for adding refrigerant.

Thanks.

 

to find out what refridgerant is in it just put your tounge on the schrader valve and press. r12 has a sweet taste, r134 not so much....

sorry about that, anyways the fittings for 134 are larger than the 12. they dont interchange. you can go to the parts house in the truck and get a 134 conversion fitting for the low side, take it out in the parking lot and compare it to the low side on the truck. i'd be willing to bet if its been in there a while it still has 12 in it. if it has 134 fittings on it, it should have 134 in it. if it has 12 fittings on it, it should have 12 in it unless someone filled it with 134 and then removed the 134 fittings (unusual but i've seen it done).

daryl

 

An AMENDMENT TO MY STATEMENT is in order, here.

There are only THREE speeds.

The switch is identicle to O.E.M.

Here is how I know:

https://www.dieseltruckresource.com/...d.php?t=155997





Now, I am really getting curious as to how I am going to know just exactly what is in this A/C system, and how I am going to find out.

While working in the cab, the son found what, at first glance, I thought was some weird male air-chuck coupler end.

On closer examination, it is an R-12/R-134 adapter, with female threads that screw on a male R-12 fitting, and has the big "air-coupler-looking" R-134 fitting, such that it is screwed onto an R-12 gauge-port and then R-134 filling equipment can then be connected.

This find brings on a whole host of mysteries.

1. It may have just been lost in the truck and have no bearing, whatsoever.

2. The A/C system may have been properly vacuumed/converted over to R-134, and, for some reason or other, this adapter must be used, rather than a permanent R-134 fitting having been installed.

3. The system may have been somewhat low on R-12 and someone used this to squirt in a couple cans of R-134, on top of the R-12. (I have seen this done, before. In fact, I had an old vehicle with R-12 and the dairy-milk-tank doctor dumped in two cans of R-134, in with the R-12 that was already in there. It cooled as cold as Christmas, until I got rid of the vehicle.)

Rather than completely evacuating the system and doing a full-blown R-134 conversion, other than guessing, how do I ascertain what refrigerant is in the system??

With this adapter in hand, if the system gets low on refrigerant, I may just go ahead and squirt in some R-134 and hope for the best.

Thanks.

 

One thing you might check, is if the air conditioner is working and is relatively cold then check the sight glass and see if it is full or if it looks real low.

My reasoning but I might be wrong is if it has R-12 the glass would show clear or maybe a bit low but if it has R-134A it should not show clear but should show rather low on charge because R-134A is only charged to 80%.

My head hurts when I think too much.
Jim