2nd Gen Non-Engine/Transmission A/C system help please.

[cumminscanuck]

This is my first post as a new member so I apologise if it's in the wrong forum.

I just topped up my A/C system with 2 aerosols of coolant but it still takes quite a while to blow really cool. I know the system was almost empty when I filled it so, is 2 cans (6 ozs each) enough to do the job or do I need to add more? If this is not the problem then I would appreciate some guidance/suggestions please.

 

[ttbird]

I don't think that 12oz is enough. But you need to get gauges and fill low side with compressor running to around 40 psi. You can buy a cheap gauge at AutoZone or the likes, for around $24. 00 that takes those small cans of 134a. Without a gauge, you are ******* into the wind on getting the correct charge in the system. Just me . 02! Check search forum for alot of posts concerning A/C problems with 2nd gens. Also need to go to User Control Panel and fill out your signature so that we will know what truck you are asking about, so our info is correct. Welcome to TDR.

 

[fest3er]

This is my first post as a new member so I apologise if it's in the wrong forum.
I just topped up my A/C system with 2 aerosols of coolant but it still takes quite a while to blow really cool. I know the system was almost empty when I filled it so, is 2 cans (6 ozs each) enough to do the job or do I need to add more? If this is not the problem then I would appreciate some guidance/suggestions please.

Hmm. Runs good, but takes a while eh? It could still be low on R134, or the evaporator could be dirty eh? (Sorry. I had to!)

Wait for a fairly hot day. Get a throttle stick and set the engine at 1100-1200 RPM. Set the A/C to fresh air, upper vents, fan on full. Add gas until the compressor stops cycling, or at least until it only shuts off every minute or three.

I don't even bother with the gauge any more. I know the A/C low side cycles between 23 and 45 PSI (or so). When the compressor stops cycling or at least runs for a long-ish time, I have enough R134 in the system and it'll stay cool (or cold) inside.

Mine also takes a minute or two to start blowing cold air. This is probably a combination of a crudded-up evaporator (lousy heat transfer into R134) and an old engine fan clutch (lousy heat transfer into atmosphere). Having a crudded-up condensor may also affect the transfer of heat to the atmosphere.

 

[Chief USA]

If you system has leaked down a substantial amount, you should add lubricating oil as well as R134. Get a set of guages and verify in the shop manual what the low and high side pressures should be based upon the current ambient temperature. The pressure will vary with ambient temp.

 

[monkeyman]

If your system was empty, it should have been vacuumed down. Also I wire the low pressure plug so it by passes the switch. You can only add coolant if compressor is running, it won't if pressure is to low connected.
Rick

 

[cumminscanuck]

Thanks for all the advice guys, I finally got some time to try out your ides today. Adding another can of coolant fixed the problem. The system was virtually empty so it needed three cans to bring it up to level.

 

[budnate]

2 cents more, also your evap coil could be real dirty, drop your fan and reach up and gently pull the crap off the face of the evap coil and blow it out with air, I read another post on here about it and checked mine as it was a little weak and found it was loaded with dirt, needles etc. . I lubed the fan and cleaned the squirell cage... man what a differance, like new again.