A buddy of mine has an old Champion upright air compressor for sale..It's been apart for nearly 20 years now..He took it apart to transport it home ..Needless to say, he forgot how the line routing was...This is an older unit, estimated age probably 40 + years old..There is a diaphragm looking device mounted to the motor/compressor platform..One line comes from the back of the pump at about crankshaft level and goes to the top/side of the diaphragm looking "Gitchie"..There are 2 other threaded openings where lines that come back out of it ..Does anyone have one of these relics in their garage?? It's about 60 gallon cap. tank , 5 h.p. motor , twin cylinder in-line pump.. 2 stage...I haven't bought it till I hear it run..Thanks....