A/C Time.

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Jan 18, 2000 | 09:32 PM

GSchretter

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From: Irving Texas

A/C Time.

On 1987 302 EFI.

The A/C is registering 10 PSI of R12

I put up to five cans of R-12 and one can of oil....

How many cans of R-12 do I have to put in this beast...

The A/C will cycles on once or twice but after that if takes about 10 mintes before it comes on again...

I check the PSI and when I first start the truck it is around 50 psi but after running the two cycles it drops to 10 PSI... If I stop the truck and wait 2 minutes and start it back up it does the same thing..

I do not think it is leaking. It acts like it is not letting the pressure go back to the low side...

Help

Thanks in advance.

Jan 18, 2000 | 10:56 PM

PAUL_2

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A/C Time.

GS ,
There is a label that tells how many Lbs and Ounces of R12 the system requires . If its not cycling on and off as required or like it has in the past , its more than likely the A/c cycling switch .... Ive replaced 2 or 3 of them on my truck . Mine wouldnt cycle off . I can honestly say the A/c in my truck is thee best A/c I have ever ... its 10 yrs old and all I have ever done to it is replace 2 O rings , they cleaned the Fixed Orifice screen ... it breaths cold air even in the hottest summer days w/o fail .
Paul

Jan 19, 2000 | 12:09 AM

sx1154

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A/C Time.

Your system is plugged up either your expansion valve or orfice (whichever ford has)is bad. Most vehicles run around 2.5 to 3 pounds of freeon.Your cans are probably 12 or 14 ounces. 16 ounces is a pound, I think 3.5 cans max would be about right.When checking the pressure you should check the high side also I like to see the pressure under 250. The low side will run between 20 and 40.

Jan 19, 2000 | 08:23 AM

Phillip Guidry

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A/C Time.

I also believe the orfice tube is clogged up. It is located,usually, at the high side inlet at the evaperator. But at the same time,if it were the orfice clogged, the metal line would freeze over at that point because of the restiction,or at any other point of restriction such as the condenser, a kinked line or even a bad valve within the compressor. Knowing the high side pressures will help in diagnosis.
Phillip

Jan 19, 2000 | 06:52 PM

GSchretter

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From: Irving Texas

A/C Time.

Replacing the Switch..

If I take the switch off will all the R-12 leak out ?

When we were putting oil in the A/C it did seem to cycle more often=.

We could not check the high side since I lost the adapter

What do y'all think about removing the R-12 and putting in R-134A ?

Thanks in Advance.....

Also is your compressure really loud when running... I can not hear in the truck but when I pop the hood it loud.

Jan 19, 2000 | 10:47 PM

PAUL_2

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A/C Time.

Gs ,
The cycling switch screws on a shrader type fitting , very little R12 leaks out as you unscrew the switch . I thought the same thing the first time I had to change mine .
Paul