 Updated The Fuel Pump..., Getting the late stype F.I. Pump to work. |
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| 74914LE |
 May 20 2012, 05:45 PM
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#1
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Member  Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895  |
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! |
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| wndsnd |
May 20 2012, 05:50 PM
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#2
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You wanted a horse, but got a goat. Nobody wants a goat.... Group: Members Posts: 2,861 Joined: 12-February 12 From: North Shore, MA Member No.: 14,124 Region Association: North East States  |
check to see you didn't reverse the feed with the return inadvertantly.
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| tod914 |
May 20 2012, 05:54 PM
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#3
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Advanced Member Group: Members Posts: 3,755 Joined: 19-January 03 From: Lincoln Park, NJ Member No.: 170 |
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.
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| 74914LE |
May 20 2012, 05:59 PM
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#4
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Member Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895 |
QUOTE(wndsnd @ May 20 2012, 03:50 PM)  check to see you didn't reverse the feed with the return inadvertantly. 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. |
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| TheCabinetmaker |
May 20 2012, 06:13 PM
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#5
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
If I'm reading you right, it sounds like the filter its backwards. Small in, large out.
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| 74914LE |
May 20 2012, 06:42 PM
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#6
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Member Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895 |
QUOTE(vsg914 @ May 20 2012, 04:13 PM) If I'm reading you right, it sounds like the filter its backwards. Small in, large out. 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! |
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| tod914 |
May 20 2012, 07:16 PM
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#7
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Advanced Member Group: Members Posts: 3,755 Joined: 19-January 03 From: Lincoln Park, NJ Member No.: 170 |
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.
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| 74914LE |
Jun 8 2012, 08:42 PM
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#8
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Member Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895 |
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.
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| 74914LE |
Jul 15 2012, 03:29 PM
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#9
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Member Group: Members Posts: 136 Joined: 6-April 04 From: Fort Worth, TX Member No.: 1,895 |
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! |
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| TheCabinetmaker |
Jul 15 2012, 03:43 PM
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#10
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Glad you got it figured out. Have you done a valve adjust, set dwell, timing, fuel pressure? All these will make a difference.
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