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Posted by: metalmorphosis Aug 21 2012, 09:21 PM

I need some help remembering how exactly the fuel lines go. The car is a 73 1.7 w stock fuel injection and pump in stock location. The pump has a S, D, and R on it and I'm pretty sure thats obviously supply, divert, and return. So my 1st question is where does the D or divert line goto? The 2nd question is that it looks like once the supply line gets to the engine it 1st goes across to the driver side to the regulator then to the fuel rails and back down to the return side of the pump is this right? Thanks in advance for any advice and/or pics.

Gabe


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Posted by: tim_nd Aug 21 2012, 09:24 PM

Off of the Jeff Bowlsby site

Posted by: metalmorphosis Aug 21 2012, 09:29 PM

Thanks for the quick responce and diagram tim nd

Posted by: tim_nd Aug 21 2012, 09:30 PM

Posted by: Racer Chris Aug 22 2012, 07:49 AM

The D stands for Druck, or Pressure in english.
I like to think of it as "Delivery"

Posted by: metalmorphosis Aug 22 2012, 06:14 PM

Just curious why the supply line would go thru the fuel rails first then the regulator?Anybody care to explain this to me?

Posted by: Racer Chris Aug 22 2012, 07:16 PM

After the regulator the excess fuel returns to the tank.
With no regulator there would be almost no pressure in the fuel rails.
Most carb setups regulate the pressure before the carbs because the system is dead-ended.
A full circulation carb setup has the regulator after the carbs.

Posted by: Dave_Darling Aug 23 2012, 12:57 AM

The regulator is like putting your thumb over the end of a garden hose. The pressure in the hose goes up when you do that, right? So the pressure regulator is like an adjustable thumb that keeps the pressure in the hose (the high-pressure loop of the fuel system) at a given pressure.

So the circuit goes from the pump, to the fuel rails, to the regulator, and back to the tank.

--DD

Posted by: 442nd914s Sep 6 2012, 07:08 PM

With the engine being removed is there a way to check fuel flow?
I have disconnected the harnest going to the pump and supply it 12 volts. I hear it working but no fuel comes out the lines (regulator and injector rail line). I have tripled checked the lines and have even compared it to this diagram and it seems to be hooked up the right way. I can also see a small amount of fuel in the clear lines by the firewall. I don't know if using a universal filter is make the difference, but I am using it (which I have also trippled checked the flow direction and its good).
As it stands right now, tank to lines, (1) line to filter, filter to pump, (2)pump return to "T" spliter to 8mm line, 1 of the "T" tines is out in the open, the injector line is also out in the open. Should I have something pluged up or removed to get fuel to flow?

Posted by: 914_teener Sep 6 2012, 07:39 PM

My 73 fuel line routes through the CSV on the 1.7 on top of the motor above the tin.

On advice......ditch those clamps that you have and get some new fuel line before you put that in the car.

Not sure why your test is not working other than the pump might be cavitating or the line near the tank is kinked or tank plugged.

Good luck.

Posted by: Black22 Sep 6 2012, 07:56 PM