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Tharf is my hero :read:
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Discussion Starter #1
New fuel pump installed because I needed more flow for the stroker.
Finally got it in and took a while to get the truck started but she ran great thereafter. It sat for an hour or so and when I came back it wouldnt start right away. I had to wait for the pump to re-pressurize the lines. I verified that the fuel was draining back into the tank after a couple times of this happeneing. I re-dropped the tank and expected to find a faulty check valve in the fuel pump. Pulled everything apart and the fuel pump check valve is working properly. There is a second check valve which seems more like a scupper flap at the base of the plastic case. I have no idea what its purpose is. There is a small T fitting in the main fuel line just after it comes out of the fuel pump and proceeds to the cap of the sender. The T fitting tees off to a 1/8" line which goes to the bottom of the case into that second check valve.

SO the question is what the hell is it for? Do I need it or can I plug it? The pump on my 1992 does not have a T fitting. It would seem to me that all you need the pump to do is push fuel out through one line. I cant imagine that the other line serves any purpose other than to piss me off. I dont want to buy a whole new sender if I dont have to just cuz of a rubber check valve. Any input on what I should do? Here are a few pics.

In this you can see the T in the main line that looks like a straw

In this you can see the rubber check valve at the base of the case.
 

·
Tharf is my hero :read:
Joined
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1,049 Posts
Discussion Starter #3
Nevermind guys, I figured out what it was. I guess its a roll over valve that would allow the fuel to dump back into the tank if the truck was ever on the roof. They apparently became a problem by building up tank pressure as they were only used for a few years and then eliminated. I will just cap it off for now.
 
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