1992 Ranger Ranger V6 3.0 A/C Refurb

[SLR_65]

Hi Guys,

My next project will be to see if I can resurrect the a/c on my '92 Ranger 3.0 V-6.

Currently it's out of gas and not holding a vacuum for long.

I'm really rusty on a/c, it's just been a very long time. I'm going to hop down to the library and grab the Haynes a/c manual, but I think I got a handle on where to start so I thought I'd bounce it off you guys and see if I'm missing anything.

*) Already did the pressure check - there is none.
*) Already tried to pull a vacuum and it won't hold.
*) I'm thinking I need to vac test the compressor to see if it's the compressor seal leaking, if it holds I move on, if it doesn't I get to buy a new compressor and then move on.
*) I could try to replace just the hose fitting o-rings but the hoses are looking weather checked so I'm thinking I'll replace them too. It's expensive to replace them with complete assemblies but from what I recall one can just buy new hose and cut the old ones off and install the fittings on the new hose and just use worm drive hose clamps, correct? Else, is there somewhere to send them to have new hoses put on cheaper than buying new assemblies?
*) Just looking at the parts available on Autozone I see it's an orifice tube system and they like to plug up easily - I was taught to replace them about any time the system was open so I'll replace it.
*) Replace the accumulator (it doesn't have a receiver/dryer, but the accumulator is pretty similar and has a dessicant pack in it so since the system has had a major leak it needs replaced). Also add a bit of oil to the accumlator (need to look the amount up, probably an ounce or so?).
*) Draw a vac and see what we have.
*) If it holds vac then charge it up with R-12 . . . yes, I still have some.

Am I missing anything?

I do have a flush gun somewhere but unless the compressor has shot craps I don't think it's really necessary to flush an R-12 system, is it? In R-134a systems the moisture that's leaked in combines with the pag oil and can make some nasties, but I don't think the moisture bothers the mineral oil in an R-12 system. Basically the moisture that's leaked in has filled up the accumulator dessicant and that's about it? Or has it combined with the oil and made a sludge I should try to get rid of?

Any and all input / direction would be most appreciated . . . again, it's been a very long time since I've done any a/c work!

This truck isn't a daily driver (yet!) so I don't mind a little down time for learning curve or waiting on parts, etc..

Thanks!

Steve

 

[exbass94]

When you vacuum it, it will boil all the moisture out of the system. You probably don't need to flush anything. The longer you vacuum it, the better.

 

[adsm08]

Replace the accumulator (same thing as a receiver/drier) and all the o-rings in the system. Suck a vacuum on it for 2 hours, watch it for 15 minutes and if it holds, cool. Shoot it up. Personally, I'd shuck out the $25 for retrofit fittings and throw 134A in it.

I threw a pound or so into my B2 on a low side charge (only have the 1 fitting) and it works fine.

 

[SLR_65]

When you vacuum it, it will boil all the moisture out of the system. You probably don't need to flush anything. The longer you vacuum it, the better.

Hi Exbass94.

I appreciate the feedback but from what I recall that's not exactly accurate. My Dad used to buy cars and fix them up and resell them and I used to help. It's been a lllooonnnggg time but some of it still sticks with me.

Lowering the pressure will allow free moisture to boil off, but moisture "tied up" in the dessicant of the reciever/dryer (or accumulator) doesn't boil off as readily. If the dessicant is saturated pulling a vacuum on it probably won't significantly decrease it's moisture content so it won't be able to do it's job of scavanging the left over moisture out of the system - this is why it's normally recommended to replace them when the system has been open to the atmosphere for any length of time and why they are shipped sealed up.

They're cheap and easily replaced so I'll replace it.

I really need to read up on all of this again . . . where did I put that copy of Modern Refrigeration and Air Conditioning anyway . . .

Take Care,

Steve

 

[SLR_65]

Replace the accumulator (same thing as a receiver/drier) and all the o-rings in the system. Suck a vacuum on it for 2 hours, watch it for 15 minutes and if it holds, cool. Shoot it up. Personally, I'd shuck out the $25 for retrofit fittings and throw 134A in it.

I threw a pound or so into my B2 on a low side charge (only have the 1 fitting) and it works fine.

Hi ADSM08,

You're probably right - start at the minimum and work my up!

I see no reason to go to 134a as I have a ready supply of R-12 (my Dad has passed away but when they were bringing 134a out he bought a boat load of R-12).

R134a is not as good of a refrigerant as R12 and usually requires a better compressor and larger condensor to provide the same amount of cooling as an R-12 system. When retrofitting an R-12 system to R-134a you will never get as good of performance. In milder climates you may not notice the decrease in performance but here on the great plains it does got HOT in the summer! The pag oil used by R-134a systems is also hygroscopic so if you get a bad leak and get air in the system it will draw the moisture to it and the resulting combination is an acidic compound that can really chew a system up.

If I didn't have R-12 handy then yeah, I'd look at R-134a just for convenience, but I have R-12 so I see no reason to use an inferior gas and get less cooling from my system.

Thanks for the input, again - you're probably right, I should just start with the minimum and work my way up. I'll post back what I discover as I get time to work on it.

Take care,

Steve

 

[exbass94]

You're absolutely right about the accumulator. I never said you shouldn't replace it, I just said you don't have to flush the lines out.