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Full Version: swapping fuel pump. from 3 hose to 2 hose...just want to make sure
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surfdogskier
Guys, I just want to make sure I do this right. Going from 3 hose fuel pump (old version) to 2 hose (newer version). The Sending line goes to my fuel filter then to my fuel pump in. My out line from the fuel pump is for my return line to the engine. I eliminate the pressure line completely.....Correct?
jcd914
As you describe it, no.

But you are using terms that I would not use and what you mean might be correct.

I don't know what a "sending line" is and if you "eliminate the pressure line completely" your car won't run.

Here is my best explanation, hope it helps.

The 3 port pump has a pressure relief valve that limits the pressure pumped to the engine, the 2 port pump does not have this.

So the 3 port pump has a suction port which is connected to the supply line from the fuel tank.
It has a pressure port which is connected to the pressure line going to the engine (injectors and fuel pressure regulator).
And it has a return port which is the outlet from the pressure relief valve in the pump. The port is connected to a "T" fitting in the return line that runs from the fuel pressure regulator in the engine compartment back to the fuel tank.

When you install a 2 port pump in place of a 3 port pump you connect the fuel supply line from the fuel tank to the suction port on the 2 port pump. You connect the pressure line to the engine (injectors and fuel pressure regulator).
This leaves you with the now unused line from the pressure relief valve in the 3 port pump that is "T"d into the return line that runs from the fuel pressure regulator in the engine compartment back to the fuel tank. You remove this "T" fitting and install a straight connector or you replace the 2 lines with a single hose.

Always use the proper high pressure fuel injection fuel hose and the fuel injection hose clamps.

Good luck

Jim

Click to view attachment

JawjaPorsche
Big line from fuel tank to filter to pump to fuel rails.

Return goes back to small line to fuel tank.

Cliff Notes version!
JawjaPorsche
Double post sorry! biggrin.gif
surfdogskier
QUOTE(jcd914 @ Sep 14 2016, 08:08 PM) *

As you describe it, no.

But you are using terms that I would not use and what you mean might be correct.

I don't know what a "sending line" is and if you "eliminate the pressure line completely" your car won't run.

Here is my best explanation, hope it helps.

The 3 port pump has a pressure relief valve that limits the pressure pumped to the engine, the 2 port pump does not have this.

So the 3 port pump has a suction port which is connected to the supply line from the fuel tank.
It has a pressure port which is connected to the pressure line going to the engine (injectors and fuel pressure regulator).
And it has a return port which is the outlet from the pressure relief valve in the pump. The port is connected to a "T" fitting in the return line that runs from the fuel pressure regulator in the engine compartment back to the fuel tank.

When you install a 2 port pump in place of a 3 port pump you connect the fuel supply line from the fuel tank to the suction port on the 2 port pump. You connect the pressure line to the engine (injectors and fuel pressure regulator).
This leaves you with the now unused line from the pressure relief valve in the 3 port pump that is "T"d into the return line that runs from the fuel pressure regulator in the engine compartment back to the fuel tank. You remove this "T" fitting and install a straight connector or you replace the 2 lines with a single hose.

Always use the proper high pressure fuel injection fuel hose and the fuel injection hose clamps.

Good luck

Jim

Click to view attachment

Thank you very much for the detailed instruction. This makes sense. Going to give it a try and post back.... pray.gif
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