the momstang rebuild begins TOOK A TRIP AROUND THE BLOCK!

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You need to put a check valve in your fuel feed line.
All the drawings I have seen for fuel systems I don't think I ever saw anything with a check valve. Does it go on the feed line, before/after the pump?

Edit - I thought about this all night. My pressure goes up the the 43 psi as i have it set at and then the pressure does slowly bleed off after the initial priming and I have been pausing between the initial key on and turning to start while I got the computer logged in and data logging turned on. Maybe it would fire right up if I turned the key right after the initial prime when pressure was high? I tried this just now but it still needed 4 long cranks to fire. I am not really sure this is the problem.
 
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All the drawings I have seen for fuel systems I don't think I ever saw anything with a check valve. Does it go on the feed line, before/after the pump?

The feed line slowly drains back into the tank over time. The check valve keeps more pressure on the line between runs by stopping this reverse flow and will allow quicker initial starts. That’s 100% why it starts quicker after you’ve been running the engine.
 
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The feed line slowly drains back into the tank over time. The check valve keeps more pressure on the line between runs by stopping this reverse flow and will allow quicker initial starts. That’s 100% why it starts quicker after you’ve been running the engine.

So before/after the pump? I could understand this theory when I am pausing between turning it on and starting but why wouldn't it start right after the 7 second prime?
 
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I might just owe you guys a beer. I have been chasing this issue for a while now. Following this theory I decided to up the time it was priming. I thought it was 5 secs, turns out it was 3, so I upped it to 7 secs and it fired on the first turn. I am not counting this chicken yet, still crossing my fingers and hoping it will start as easy again this afternoon....
 

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You guys all beat me to it. Had the exact t same issue when I had my blown nova years ago. It was bleeding back into the tank and I had to let it prime a little longer before starting it. Never thought about trying check valves.


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well after letting it sit all afternoon it fired up faster then it ever has before tonight. Looking at the data log it fired up in less then half a second(literally .44 secs) so that is pretty fawking cool. At this point, 2 times in a row its an upward trend if it fires up again tomorrow I will finally be able to put the wheels on the ground and go for a spin. How long of one will depend on the brakes... Cross yer fingers folks could you imagine a driving pic or vid?
 
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once again it started up easily so I put the wheels on the ground and took 2 laps around the block. Good news = it starts, gooder news = it stops too! I took the time to bleed them one more time since it was off the ground and I must have got the last bit out. Bad news = the steering still sucks. I almost think my K is off a bit as it looks like the passenger side sticks out little further than the drivers.....
 
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You’re welcome.
I am thankful, and annoyed that the valve and fittings will run me $80. But it was kinda fun to feel like the pied piper as after the 2 trips around the block a gear head neighbor that is down the street came down to hear it up close.
 

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I don’t really see the need to add the valve if you can just leave the prime timer turned up. It won’t hurt anything to have it priming a few more seconds.


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There really isn't a big deal with doing it short of having to wait and count 7 secs as though your starting a diesel that I can think of. But looking at the valves and knowing how I ran everything I am pretty sure I can add it as easily as disconnecting the line and inserting the valve.
 
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so I got the check valve in today and was really happy that the install was as easy as I hoped it would be. I primed the line with the current 7 second prime that has been working and then turned the time down to 3 secs for the next time I turned the key. Then I took an hour off and checked the pressure a couple of times and saw that it was still dropping, although slower now. So after an hour I went back and it took 3 times to get the car started. I wasn't sure that the feed line was what needed the valve since the an fitting fuel hat I use the return line I know is just a straight pipe into the tank. The feed line has to drain through the pump and filters at least, the return is just a straight shot into the tank so why isn't it the return line that needs the valve?
 

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