Don't Know How Much Refrigerant My Truck Takes

['89RangerBoi]

Hey everyone,

I'm recharging my truck's ac system, but I don't know how much refrigerant it takes. The tag that's supposed to be in the engine bay isn't there (I believe it came off when a previous owner had it, as there are marks where other stickers have been). I have a 1989 Ford Ranger XLT (4x4) with a 2.9L V6 engine. I was wondering if anyone has the same truck and could check the sticker on their car for me, or if anyone happens to know how much refrigerant my car takes anyway. Thanks, all.

By the way, I believe the system was already retrofitted to accommodate an r134a system, so I will be using that refrigerant.

Thanks.

 

[Uncle Gump]

So I moved this post and deleted your second. There is only need for one post on a given topic.

I'm cooking some dinner but if you don't have an answer when I'm done... I'll try to help you out

Sit tight... many here are pretty well versed in these A/C systems.

 

[Uncle Gump]

So is it completely empty?

Did you change parts?

Repair leaks?

Pull a vacuum on the system?

Do you have a/c gauges?

 

['89RangerBoi]

I bought the truck with the ac compressor out, so yes, the system is completely empty. The ac compressor came with the car. I was planning on renting a vacuum pump and manifold gauges to clear out the system, and then recharge it with the correct amount of refrigerant.

 

[Uncle Gump]

Gotcha...

If the system was open for any length of time... or especially if the compressor blew up... you should really flush the condenser evaporator and lines. There is likely junk in them. You really need to replace the accumulator and the orifice tube also.

Did your replacement compressor come with oil in it?

 

['89RangerBoi]

I don't believe it has oil in it.....

Any particular flush I should use?

 

[Uncle Gump]

I'm also gonna ask @franklin2 and @RobbieD To jump right in. My Service Manual on CD like self destructed so I don't have access to the actual fill amounts.

 

['89RangerBoi]

Thanks!

 

[lil_Blue_Ford]

Yup, everything needs flushed and you need an accumulator and orifice tube. You also will need adapter fittings if the truck doesn’t already have it to go to R-134a. Original for your truck was R-12 and a mineral oil charge. It’s no longer available so you need PAG-46 oil if memory serves correctly and R-134a for the charge. I don’t have the amounts you’ll need handy, but I believe it’s something like 8oz of oil and three 12oz cans of R-134a but you’ll actually only use two cans and a partial.

 

[Uncle Gump]

I don't believe it has oil in it.....

Any particular flush I should use?

Most box stores have flush kits and any of them should do the job.

 

[RobbieD]

The AC system sticker on my '90 is right on top of the evaporator housing on the firewall. I've also looked up the charge and oil charges in the 1989 shop manual for you.

Refrigerant charge capacity in the 1989 manual calls for 32 ounces of R-12. On a converted system a rule of thumb calls for 90% of that, or about 29 to 30 ounces of R-134a.

The oil charge is listed as 10 ounces. As mentioned, mineral based oil and PAG are not compatible. In case of a leak or component replacement, you can either drain all of the oil or estimate the loss from a leak or component replacement and add that estimated amount.

A new accumulator and orifice tube is the norm.

I believe the system was already retrofitted to accommodate an r134a system, so I will be using that refrigerant.

I hope that the system was retrofitted, and done right. Tough call on what to do here. You could just charge it with 134a cans which include oil and see if the system actually works.

I'm just leery about putting too much stock in a system that is said to have been converted. Did you dump the charge yourself, or did you get the truck with it needing a recharge?

If the system wasn't converted properly, or not flushed completely of the original oil, it won't work properly, or just flat-out fail. In that case, any new parts that you put on it, like the accumulator and orifice, will be wasted money. And, in that case, you're pretty much looking at replacing everything to get it right again.

A good, trustworthy shop that does, and knows, older Ford AC systems may be worth considering in this situation.

 

['89RangerBoi]

Thanks for the help. I was planning on playing it safe and just flushing and vacuuming the system just in case it hadn't been retrofitted.

 

[RobbieD]

Good luck. I hope that it goes smooth, and gets you back into the frosty chilly breeze.

 

[Danny74]

Well first I got to say it's only been a few months but I hope everything worked out okay for you on your AC system repair. I came across this looking for info on my repair job but I thought I'd mention something for somebody else who came looking and found this thread in the future.

........ I was planning on playing it safe and just flushing and vacuuming the system just in case it hadn't been retrofitted.

Well you can just tell by connectors! If it had been retrofitted they would have changed the connectors to the ones that accept the R134a clip on styleports, the old R12 systems had a Schrader valve that looked like a tire valve stem, where the hose would screwed on, instead of a Clipped on like the r134a.


I'm getting ready to charge assisted in my 1995 3.0 ranger. I had a problem last year and I added the dye and a little bit stop leak, and it worked fine all last summer but it's not working this summer and I noticed on the high side valve the glowing green fluid that indicated the leak. The ball valve is actually bad. I don't know why Ford did that they put a ball valve in a high side and a Schrader on the low side, so you can't just replace the inner valve piece you have to replace the entire about port, and to top it off you need a special eight sided socket, so I could have bought just a high side or low side for 17 bucks, or the pair for 25 bucks. So I got the pair, because the high side is fatter than the low side. Just swapped out the valve port on the high side with a $7 valve port that I got on amazon, now I just got to find out how much refrigerant I need to put in it so I can buy the correct amount of our 134a. Somebody told me it was 22 1/2 oz but that's going to be annoying because they come in 12 oz cans, and I don't want to have to buy a scale

 

[Danny74]

Update:
Did the repair and recharge. However it did not take more than (2) 12oz cans of refrigerant. Infact, the presure guage was almost at max before I was even finished with the second can.