Team Chevelle banner

How do I prime my fuel system?

2556 Views 10 Replies 7 Participants Last post by  zeke67
I would like to check for leaks before starting the engine. The Chevelle has been sitting for over a year. During that time, I replaced the fuel lines between the mechanical fuel pump, regulator, filter and carburetor. These are all double flare aluminum, so I really want to sort out leaks and makes sure the flares are good. I could rig up an electric pump as a "puller", but can I pull fuel from the tank though the mechanical fuel pump?
1 - 2 of 11 Posts
if you're careful you can do what I do: I use a an air nozzle, wrap a rag around it, stick it in the filler neck, GENTLY pressurize the tank. this will push fuel to the front, fill the carb and even give a pound or two of pressure in the entire line. That will help check for leaks between the tank and pump.

Obviously, this would not be a good time to do something unfortunate like blow up the tank or something. You can start with a couple small tests, you can feel the air pressure coming out as you pull the rag/air nozzle away, get an idea where you're at.
if there's a vent it'll need to be pinched off. I have some small needle-nose Vise-Grips that work well for this.

Yes, it'll push right through the pump. the pump is just two sets of check valves.
1 - 2 of 11 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.