240z losing prime while sitting

[zach89]

hey guys newer to the carbureted Z cars. i’m seeing if anyone can help me with the issue i’m having. i got my 71 240z mainly stock up and running but after it sits for hour or two i have to prime the fuel system again by taking off the return line and blowing back into the tank to fill up the fuel filter. it’ll run fine but soon as it sits the fuel drains out of the filter and won’t start. i replaced the lines going from the tank to the hard lines and the fuel lines in the engine bay. Also has a new mechanical fuel pump. i blew from the hard lines in engine bay the the tank and air comes through easily. Any ideas ?

[NewZed]

27 minutes ago, zach89 said:

 Also has a new mechanical fuel pump. i blew from the hard lines in engine bay the the tank and air comes through easily. Any ideas ?

 

There's a couple of long threads on classiczcars.com about how the new aftermarket fuel pumps are bad right out of the box.  Poor seals.  They don't pump well and they don't seal when they're off.  Which pump did you get?

 

It's a problem and there doesn't seem to be a brand that is guaranteed to work.  

 

Classiczcars is down right now but when it  comes back I'll see if I can find a link.  One of the guys really went deep in to the guts of the pumps and has found solutions.  zKars, I think.

[zach89]

the previous owner replaced it right before i got it. i think it is bad though, i just now took it off and there was oil inside the pump also one of the gaskets was all deteriorated and ripped up. i’m gonna order another one but idk which one will be the best choice