91 fj A/C revival: a plea for information (1 Viewer)

[91fj newbie]

91 fj(ol blue) bone stock & beat up. Just replaced H2O pump & got intimate w/ front of engine. Anyway, all pieces of a/c present. Assuming compressor & clutch are operational what do I need to do to make my a/c work? I confess complete ignorance in the realm of auto a/c.
A/C system was disconnected @ purchase ( no belt installed). From what I understand it probably ran r12. System has not been in use during my ownership (3yrs) & probably much longer. What do I need to do to have conditioned air? It gets quite hot in S. Az. Any help would be greatly appreciated. Thanks in advance.

 

[Rusty Marlin]

Oh boy. What you have asked for is a full class in A/C and I am not a master.
Quick start: you can convert it to R134, but its been disconnected for so long there may be damage especially if its been depressurized or open to atmosphere.
You may need to replace the whole system, or you might be fine to do a refrigerant conversion; without a thorough troubleshootng and examination of the system anyone would be shooting in the dark.
My suggestion would be to Start at 1 and work your way through this chart.

https://www.sanden.com/originals/objects/System-Diagnosis-Chart.jpg

The Sanden site is a phenomenal resource.
Read the following and work through until you know enough to fix it or call "Uncle".

https://www.sanden.com/objects/3_-_Troubleshooting_-_Web_01.pdf

https://www.sanden.com/originals/objects/AC_Compressor_Guide_and_Practical_Tips.pdf

 

[91fj newbie]

Thank so much! Looks like school is back in session.

 

[leonard_nemoy]

1. Go to a shop and have them do a vacum test on the system and identify any leaks.

2. Replace any seals, O-rings or leaking parts.

3. Get the system charged with shop air to ensure your hoses won't burst when you recharge it with expensive refrigerant.

4. If nothing bursts or breaks or anything that did fail is replaced and all leaks are fixed than try to find somebody with some R12 and get it recharged with R12.

This is what I did with my 91 a few years ago and it was in a similar situation to your 91. Its ac had not worked in years.

I only had to change a few O-rings and the high pressure hose. Than with new R12 it worked great!!!! R12 will blow colder than the newer gas.

As others mentioned you could also replace the entire system and use the new refrigerant.

I also know a few people that use propane as a refrigerant in their old R12 vehicles.

I am sure this comment will start a whole side discussion about the dangers of using propane because it is flammable. Even though the newest refrigerant 1234yf stuff is flammable......

 

[Rusty Marlin]

You won't get any aguments out of me on the propane/R12 replacment.
It's about 2# of propane, compared to the 200# of gasoline you're sitting on, its not a big a deal.
RV refrigerators have been running off propane for probably well over 70 years, and the amonia gas will get you be for the propane does.

 

[91fj newbie]

I can't tell you folks how much I appreciate this info & this forum! This is invaluable & empowering info! Thank you Mudders!

 

[91fj newbie]

If requested perhaps I'll do a write-up of this journey back to conditioned air.