Ok, as stated in an earlier thread, I was inquiring about converting my A/C over to R134-A. Well, as it turned out, I ran into the previous owner and he told me hes already done this but it does have a leak somewhere and that a can should last a month or so. So today I buy an A/C gauge, hose w/proper fittings and a can of R134-A leakstop/dye (leak detectant and sealant) as well as a couple regular cans.

When I initially checked the pressure (while running and a/c on for a few) I get 0 psi. So I add the leak stop/dye R134-A. I check it again while running and a/c blaring and get like 20 psi. Ok, so according to the gauge check guide it needs more. So I add another can then my compressor starts clicking on and off like every 3-5 seconds. Profanity Removed? I go to check the pressure after the second can and it goes from 50 psi (right where it should be) to like 20 psi, depending on whether the compressor is clicked on or off. No *red* leaks were found either.

Why is this happening?? My a/c is still luke warm . I don't want to drive like this for much longer. Its damn hot where I live and its only going to get hotter All input appreciated!

 

OK, tried to you earlier you need to add at least 3 to 4 cans so the compressor will stay on. If you look at the Accumalator/Dryer you will see a connector with two wires going to it. This is the low pressure sensor and it won't let the compressor run with no freon(which causes it to burn up) so add a can or two more and look for the leak. I gave you a good place to look on the condensor look at the old post where I told you to look 1st, Good Luck!!! Be sure to add more freon so you don't burn up the compressor.

Rick
86 302 EFI, bored 60 over, AOD,
Headman Headers, Flowmaster 40 series,
2 inch dual exhaust, MSD ignition

 

Rick,

After the second can, it was bouncing off 50 psi. This is the max it should be according to the gauge instructions. I don't want it to be over-pressurized and cause damage. Should I keep going anyways?

 

Are you hooking the gauge up to the right side of the compressor? Sounds like you hook the gauge to the High pressure side (this is going from the compressor to the condensor and then to the dryer and then to the evaporator) and not the low pressure side (BE VERY CAREFUL THE CAN OF FREON COULD BLOW-UP ON YOU IF YOU ARE ON THE WRONG SIDE!!!!!!!!) . You want the suction side this is the side coming out of the evaporator (which is inside the truck) and going back to the compressor this is the low or suction side (look at my gallery and the picture of my engine and on the left side of the picture you see a round black cylinder this is the dryer and if you look close you will see a blue cap this is the low side connection) and should read any where around 27 to 40 lbs. depending. My truck took 4 1/2 cans (12 ounces) and one can of oil charge to fill up. Another way to check you system is to look at the sight glass which is on the passenger side right near the radiator on the high pressure line. when you look at the sight glass you should not see any bubbles or foam it should be a clear looking fluind flowing. Why don't you email me and we can talk more on how to check and fill your A/C.
Rick
86 302 EFI, bored 60 over, AOD,
Headman Headers, Flowmaster 40 series,
2 inch dual exhaust, MSD ignition

 

C.M., I converted my '88 Bronco to 134A refrigerant, about three years ago. Within the past year, I had to add 134A occasionally, due to a minor leak. As in most cases, a minor leak over time turns into a major leak ... that happened last week when I topped off with 134A and it lasted only about four days. My problem turned out to be a leaking "evaporator core" ... this part is located in the large plastic housing attached to the firewall, on the passenger side. Usually, a simple way to detect a leak in the "evaporator core" is by rubbing your fingers on the bottom seam of the case ... if you detect "refrigerant oil residue", there is a good chance the core is leaking. When I removed my old "core", it was about 85% blocked with enviromental debris (one side only), so I don't know how my a/c system was cooling farely well when charged properly. I installed a new evaporator, which I purchased from Autozone for $90 bucks. Pulled a vacuum for 30 minutes, then recharged the system with approximately 30 oz. of 134A. When properly charged, my manifold gauges showed 30 psi on the low side (blue gauge) and 225 psi on the high side (red gauge) with an ambient temperature of around 89 degree.
I'm not a mechanic, but completed a 3 month refrigeration coarse many, many years ago. :-) Hope this info helps ... John

 

[updated:LAST EDITED ON 29-Apr-02 AT 08:33 PM (EST)]Thanks for the info guys. Rick, before I jump to conclusions on anything I'm going to take it to a master tech friend of mine tomorrow and have him hook up on the high side to find out what the problem is. I just talked to him and I know I was doing what I could with what I had and I was definately filling up the low side. I will post back here with a conclusion tomorrow.

 

Good Luck, Hope there's nothing major wrong.

Rick
86 302 EFI, bored 60 over, AOD,
Headman Headers, Flowmaster 40 series,
2 inch dual exhaust, MSD ignition

 

:-X23 Damn I'm stupid. It was just low and I was just too chicken s**t to keep filling it up even though it was bouncing off 50 psi. Luckily, nothing bad though. Nice and cold now . He said to find the leak put a black light under the hood while dark out for my not-so-obvious leak. He said it should glow. Has anyone tried this successfully before?

 

How difficult is it to do the 135 conversion???

 

Read this thread:

https://www.ford-trucks.com/dcforum/bigbronco/2262.html. Rick explains it.