anyone know wich one is the low side for the 6.9 ? My compressor spins freely by hand so im sure it just needs a charge and done this tons of times but not to a Ford ... can anyone help and about how many 1lb cans will out system hold ?

 

The low side port is over by the accumulator.

I converted my 83 to 134 and I put 4 lbs. in it. It cooled great.

 

is that the tank looking thing on the left hand side if your looking at the motor.

 

Thats it....

 

My 1989 takes 3lb.4oz. I put in 4 12 oz. cans. I read somewhere that your suppose to put in 80% of 134 Mine will blow 38 deg. air with 75 deg.outside temp. standing still.

 

I have converted several systems and we first tried to use the % thing. We learned that every vehicle is different. AC is precision guess work. To many variables involved.

The new vehicles out now are tough to work on or next to impossible without a new machine. A tenth of a ounce is critical now.

 

when installing 134 be sure to add the proper amount of PAG oil or ESTER
the mineral oil used with r-12 is not compatible with 134
and when using 134 it has a tendency to expand as the system heats up
you could always charge an r-12 system to the correct pressures qucikly and you were done
but if you try it with 134 the pressures will continue to rise as the system heats up and then it is overcharged and an overcharged 134 system wont cool either

 

nearly forgot . the way you can identify the pressure fittings is that the one on the smallest a/c line is the high pressure and the low pressure is always on the large line or teh accumulator located in it

 

Yep, If you have a good set of gauges for the gas you are working with you can get one charged right. Our a good set of gauges and a conversion chart. But you have to watch. Some machines have pressures that are not "normal". The low side will be but the high side can be low compared to cars and trucks, especially trucks with on/off fans. I have seen great working systems with high side pressures on 90+ deg days in the 150's.

 

ahh ok well guys i got a 6oz can of oil/stop leak and 2cans of Subzero and 1 can of cheap stuff so ill let you know how it goes tomarro.

 

I wouldn't use the stop leak stuff. It makes a mess of a system. I would gas with dye in it. Then black light the system. Stop leak can cause problems.