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Discussion Starter · #1 ·
I bought a recharge kit and I am going to get my ac blowing cold again. My question is, where is my recharge location in the engine bay? Any tips on this procedure?
 

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On my 88 Trooper (2.6) it is under the battery, and a real knuckle buster to get to.
 

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First off, there are 2 lines. One low pressure; one high. If you connect to the wrong one, the can might explode in your hand or face.

Secondly, a lot of folks assume that because an a/c system isn't cooling that it's low on refrigerant. That may be the case, but not always.

The only way to determine what's going on is to hook up a set of gauges designed for the refrigerant in use. R-12 and R-134a gauges are different.

After the gauges are hooked up, you must interpret the high/low side readings. These readings will tell the story.

One needs training in order to do this correctly.

It would be best to pay a shop to hook up some gauges and tell you what they see.

If you hook up one of these "kits" and low refrigerant is not the problem, you'll over- charge the system. There is a high pressure switch in the circuit that detects excess charge. When this happen, your system "short cycles" or turns on and off rapdily and cooling never takes place.

Again, just because it's not cooling doesn't mean it's low on juice.
 

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The first thing you do is take a small paint brush with some dishwashing soap mixed with water.Trace all the a/c pipes and brush with the soap over the pipes.This is the best way to find if your pipes are leaking.If you see any bubbles then you know that your pipes are leaking and need to be replaced.Check the connectors aswell.The charging valves are located on the compressor(R12 SYSTEM) or on your pipes(R134a SYSTEM).To determan which system you have is to look at your charging vaves.The R12 system has screw on valves and the R134a has clip on valves(the place where the charging pipes connects on.DON'T ever mix the two gasses together.This will form a sticky fluid witch will seeze up the compressor.If you charge your system start your truck and rev it at about 2000 rpm.Charge the system very slowly until you reach a temp of 7 degrees at the vents.Find out what the low and high presure must be before you charge your system.It will be in psi or kpa or bar.
 

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Discussion Starter · #5 ·
Charging was a success. I used a kit for the low pressure side. The previous owner had converted from R12 to R134a. It was definitely low on coolant. I went ahead and added dye as well so that I can find the leak. I was nervous when adding the refrigerant for the first time, because the bottles were forming frost on the outside. My final pressure reading, after adding two bottles, was around 30psi. Which is perfect.
 

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TexasTrooper said:
I was nervous when adding the refrigerant for the first time, because the bottles were forming frost on the outside.

This is normal. You can help speed up the feeding and reduce the exterior freeze up by wrapping a rag soaked in hot water around the can before you begin.
 

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Discussion Starter · #7 ·
Thanks Mike
 

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yea, what kind of a/c type are on troopers with 2.6? R134a? or the other, R-12?
 

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Discussion Starter · #9 ·
Mine is an R134a conversion
 

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IIRC, Isuzu did not start using R134 until some point in 1993 for their AC systems. My 93 Trooper RS came originally with R12. Others have stated their 93s came with R134. There must be a cut off somewhere in that year....
 
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