I'm in the process of putting back together a 72 suncoupe and Im looking for some help with the vapor line plumbing. Does anyone know the correct plumbing for the four lines that leave the the vapor separator behind the back seat? I did label the lines but didn't label the tank and im not sure anymore what goes where. Does anyone one have a skematic? I have all the lines but its been about 5 years since it was disassembled.
There is a diagram in the 72 Buick Chassis Manual, page 80-8. I'll try and scan it for you later if need be, but you really should have a copy of the Manual especially if you are restoring a GS. It's not like they aren't readily available. Basically, if you look at the vapor separator, there are 3 pipes grouped together on the passenger side. Those 3 connect up to the tank vents in the same orientation as they leave the separator. The remaining pipe on the driver's side of the separator goes to the hose up to the charcoal canister behind the headlight.
hers'e the 72 manuals the drawings are in there - 71 the line with yellow line has an orifice built into it (think that went away in 72 -so double check) <center> </center> 1972 full Buick Chassis Manual - GM Corp <center> </center> 1972 full GM Body Service Manual - - GM Corp
The 72 still has the plastic orifice insert in the rubber hose. I have take them out of junked 72's. This is on the end of the hose that comes from the frame mounted long vapor line. Most of these got thrown out.
