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-   -   a/c issues where should i start??? (http://www.peachparts.com/shopforum/diesel-discussion/299648-c-issues-where-should-i-start.html)

richclan 05-31-2011 07:38 PM

a/c issues where should i start???
 
i have owned this car for 4 years and the a/c has been very good until this year. i would say it blows at 70 - 75 deg now at center vent.

the ac clutch engages with no issues

lots of bubbles in the sight glass

i looked at the lines and dont see any oily connections, high pressure lines are blue

aux fan runs good even before i start it up

factory r12 charge i believe, because the car has less than 60K on it.

i dont want to convert it after reading many posts on the subject.

thanks

vstech 05-31-2011 08:31 PM

start with a set of gauges and measure the pressures at operating temp.
also, check to see if the aux fan is operating.
also check the condition of the front coil for damage and clean it.
once this is done, go online and take the open book 608 test, then go to napa and get some R12.

richclan 06-01-2011 11:31 AM

ill have to ask around for the gauges i dont have any

some threads stated that i could add r12 until the bubbles disappear in the sight glass

and if i used the freeze 12 instead of r12 whats the story on that stuff???

oh and its the 609 test for cars

thanks

vstech 06-01-2011 11:41 AM

adding R12 without knowing your pressures is not wise.
best to get readings first.
if you just want to ad 12 in until the bubbles go away, you should THOROUGHLY clean the condenser, and verify the aux fan is working properly, and set a large blower in front of the car prior to checking for bubbles.

richclan 06-01-2011 12:04 PM

aux fan is good to go and the condenser is very clean, see right through it and the radiator

also am i missing anything else to test???

richclan 06-03-2011 02:27 PM

forgot to ask what pressures are needed on the high and low sides.

i was lucky to find a friend with gauges and some old r12 freon :D

leathermang 06-03-2011 02:31 PM

The FSM warns about using the sight gauge to fill refrigerant...
there is a possibility of it indicating need for more refrigerant when it is already full... few things worse for an AC than having too much refrigerant since CHANGING from one phase to another is the basis of the physics... so a proper differential in pressure needs to exist... that is taken away by too much refrigerant...
Fill by pressure and vent temperatures...or .. if a new fill... but accurate weighing of the refrigerant.

richclan 06-03-2011 03:07 PM

Quote:

Originally Posted by leathermang (Post 2728683)
The FSM warns about using the sight gauge to fill refrigerant...
there is a possibility of it indicating need for more refrigerant when it is already full... few things worse for an AC than having too much refrigerant since CHANGING from one phase to another is the basis of the physics... so a proper differential in pressure needs to exist... that is taken away by too much refrigerant...
Fill by pressure and vent temperatures...or .. if a new fill... but accurate weighing of the refrigerant.

do you know what pressures are needed for the high and low

tangofox007 06-03-2011 03:32 PM

http://www.ackits.com/aacf/ptchart.cfm

richclan 06-04-2011 12:34 AM

thanks tangofox007 exactly what i needed :D

richclan 06-06-2011 06:50 PM

added 2 cans of r12 with gauge readings in spec. road tested and its nice and COLD :D:D

thanks guys

vstech 06-06-2011 06:52 PM

Quote:

Originally Posted by richclan (Post 2727421)
aux fan is good to go and the condenser is very clean, see right through it and the radiator

also am i missing anything else to test???

the ability of light to pass through a coil does not insure the coil's ability to transfer heat.
I said CLEAN the coil.

vstech 06-06-2011 06:54 PM

Quote:

Originally Posted by tangofox007 (Post 2728731)

that link goes in my sticky


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