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There is a vacuum line stub running off of the fuel pump facing in the direction of the firewall. Nothing is connected to it. What should this be connected to? Pictures would be worth a thousand words. Thanks in advance.

Yes, a picture regarding your question might help......Without that I can only guess. If you have a 2 stage fuel pump.....bottom part of the fuel pump, pumps gas, and top diaphragm supplies vacuum to the vacuum operated windshield wipers. If you have vacuum windshield wipers, then that attachment might be the "line stub" to connect vacuum to the wiper motor. However, you mention only 1
"line stub" at the fuel pump, should be two "line stubs" viewable. If not, seeing 2 ports, then one of the pressed in vacuum line stubs may have been lost. The ports are just pressed into the pump. Hope this helps.

Steve

The vacuum portion of the fuel pump is in series between the intake manifold port and the wiper motor. Normally the intake manifold provides all the vacuum needed to work the wipers. The intake manifold is stronger than the pump so the pump valves are kept wide open letting the manifold pull thru. On occasions when engine vacuum is low such as when the engine is under load or the throttle is well open the valves in the vacuum pump will start working letting the pump take over and provide enough vacuum to keep the wipers moving. Because the pump does not have the volume capacity the wipers will usually move at a slower pace.

Unless someone has an engine out I suspect getting a decent photo of the tubing will be difficult. Until someone posts one here is a photo from the 54 fact book showing the lines. I took the liberty of coloring the approximate routing in the second photo but the exact side by side layout of the tubing and hoses could vary depending on pump model. The ports on the pump should be labeled in and out. If no labels, OUT or the port with pressure when engine is running goes to the manifold and IN goes to the wiper motor.

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