Classic/Antique Car Repair: vacuum lines 61 Rambler, vacuum unit, vacuum lines

Question
Have a fuel pump / vacuum pump on a 6cyl (196) AMC Rambler. Their are four outlet on the vacuum pump. Were do these line go? I assume one may go to the vac adv on the dist. I have a open fitting on the carb which may be for a second line.

Thanks

Answer
This pump should be split into an upper chamber and a lower chamber, each with two ports. The lower chamber is the fuel side and the upper chamber is the vacuum side. The distributor picks it's vacuum directly from the carburetor ported vacuum fitting. This is the port on the carburetor that will not have vacuum unit you open the throttle and at light cruise, about 1500 RPM, this port will have vacuum. One side of the vacuum pump goes to the intake manifold and the other side goes to the windshield wipers. The purpose of the vacuum side of the pump is to supply constant vacuum to the wipers when the engine is under heavy load like climbing hills. To check which line is which on the vacuum side, run the engine. Place you thumb over one of the ports and you will either feel  vacuum or pressure. If you feel vacuum this is the side that goes to the wiper motor. If you feel pressure this is the side that goes to the intake manifold.