So close to having a/c

[tunedis95]

on a 1990 nissan 240sx using s13 sr20det ac pump. i have all the lines hooked up....i just connect that drier connection and the one on the ac pump and thats it???

when i turn on the ac the light does not come on....the ac is not charged yet could that be why???

......how many cans of the r12 stuff do i need????

yes i'm going to use r12...got a hold of some....

[kensreliableb18b]

yes, you have to charge, otherwise the pump will not engage and the light wont turn on.

[tunedis95]

alright....thats one question down.......

how many cans????

and only two wires are connected in the engine bay (for the ac pump and drier)????

[hipro]

How many cans? The FSM says that the total system capacity is 1.8 to 2 lbs. of Freon 12. The small cans are normally 12 oz, you could need up to 3 cans. By the way, don't forget compressor oil! The FSM also says that the total oil capacity is 8 ounces, but keep in mind that your old compressor probably still had some oil and some oil is normally distributed in the other components (condenser, for example). What I have done is to only add 4 oz. of oil and then started with a single can of refrigerant (I use R134A), which is usually enough to pick up the low pressure switch to allow the compressor to operate. After putting in one can of refrigerant, run the A/C for a while and see how it performs. When functioning properly, the small high pressure side pipes (from the compressor to the condenser/front of the car) should feel hot and the larger low pressure/suction side pipes (from the evaporator/cabin returning to the compressor) should feel cold. If you aren't getting the cooling effect you are after, add more freon. With too little freon, you can normally see lots of vapor bubbles in the sight glass on the liquid tank (by the battery, where the dual pressure switch is located). With the right amount of freon, there should be a substantial temperature difference between the suction and discharge piping and you should also see some vapor bubbles in the sight glass. If there are no vapor bubbles present, you have probably added too much freon, so go slow and be deliberate in the amount being added.

[tunedis95]

your awsome dude...thats what i'm talking about....useful information.....thanx.....

[Muzzy]

y doesnt your monkey ass use r134??