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Posted by: 74914LE May 20 2012, 05:45 PM

Before I spend much more time trouble shooting, I thought I would seek some wise advice.

The 74 2.0 ltr. (Fuel Injected) had been sitting for about 4 years when I baught it. First task was to:
- clean out the fuel tank, including screen.
- install stainless lines
- replace all the hoses
- installed new fuel filter.
- cleaned all the electrical connections.
- validated the fuel pump circuit.

After validating that the pump needed to be replaced, I decided to update to the 75-76 late stype fuel pump, just to get it running again. To quickly move it along, I put the new pump in the same spot below the battery as the old one, just had to modify pumping for the two fitting pump. After installing, when I engage the ignintion, the pump runs for a couple of seconds and then cuts off as it should.

The problem is that I am not getting any fuel to the top of the engine. After engaging the circuit a few times, I cracked open the delivery line, and I heard a pressure sound, like it had a vacume on the line. The return line from the pressure regulator has nothing in it when I open it up. I have validated that fuel is getting
to the pump, but it is not getting through it. I wired into the normal fuel pump electrical socket. Any ideas to determine why it might not be getting fuel?

Thanks in advance!

Posted by: wndsnd May 20 2012, 05:50 PM

check to see you didn't reverse the feed with the return inadvertantly.

Posted by: tod914 May 20 2012, 05:54 PM

Swap your wires, maybe it's backwards? I take it your getting fuel to the filter? That is also directional. Pump might need priming. You can fill it with gas and that should do it.

Posted by: 74914LE May 20 2012, 05:59 PM

Thanks. I checked that one, and Since there is a 7mm and 9mm SS Fuel Line, I have the 7mm line running straight up to the Pressure Regulator, and with the 9mm line, it is running into the fuel filter(Since it is a late model filter, it has the small input and the large output, so I created a stepdown adapter) and then into the large input side of the fuel pump. Let me know if this not correct?

Is it possible to reverse the polarity on the pump? I will check this the next time I am under there, but I recall running the negative to the BROWN ground side of the fuel pump plug.

Posted by: vsg914 May 20 2012, 06:13 PM

If I'm reading you right, it sounds like the filter its backwards. Small in, large out.

Posted by: 74914LE May 20 2012, 06:42 PM

I believe I have the filter lined up correctly. There is a directional arrow, and the large end of the filter is going into the large end of the pump. Priming the filter and pump will be a step as well. Assumed that since there was fuel in the line, that it would feed through. Will also verify the polarity on the wiring. Hopefully it is just a few more simple steps to success.

Thanks!

Posted by: tod914 May 20 2012, 07:16 PM

The pump needs to be primed from the small end. The end that goes into the engine bay. At least you know the line isn't clogged. Can you post a shot how you mounted it? Maybe also post or illustrate your fuel line routing. Like the other guys said, very easy to get them swapped.

Posted by: 74914LE Jun 8 2012, 08:42 PM

Thanks for the advise on the pump priming. That was the issue. Fuel Flows now. Now the fun part of getting the ignition sorted out.

Posted by: 74914LE Jul 15 2012, 03:29 PM

Engine starts and runs, but will not hold an idle, and will not rev past 4000 rpms. It runs great between 1500 and 3500 rpms. Any ideas before I start running down the checklist? Hopefully someone has seen this before...

Thanks!

Posted by: The Cabinetmaker Jul 15 2012, 03:43 PM

Glad you got it figured out. Have you done a valve adjust, set dwell, timing, fuel pressure? All these will make a difference.