A/C low pressure side?

[gr8ful]

Does anyone happen to know which port is the low pressure side on these compressors?
Thanks!
Abe

 

[pithicus]

it will be the black one top of pic with the bigger pipe.

 

[gr8ful]

Thanks!

 

[John Young]

You can get kits from Amazon to convert over to the quick connect type used with R134A. I think you may need to change the expansion valve at the same time (I assume the 70 has an expansion valve adjacent to the evaporator like the 80 series, but I don't actually know.)