Fuel Pump - Need Help, trying to fire up my barn find for first time...no fuel |
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Fuel Pump - Need Help, trying to fire up my barn find for first time...no fuel |
willimac |
Sep 14 2014, 07:48 PM
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#1
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Newbie Group: Members Posts: 14 Joined: 14-September 14 From: minnesota Member No.: 17,901 Region Association: None |
I'll try to keep the story short. I have a '74 1.8 L-jetronic 914 that I rescued from a barn in central Wisconsin almost 3 years ago. It had sat for over 20 years and become a palace for generations of barn mice, who built nests in every available cavity. Since then I've been sporadically cleaning it up, vacuuming mice and their nesting material, dropping the engine, dismantling and rebuilding it, cleaning up rust, shopping new parts (alternator, starter, stainless fuel lines, seals and gaskets) re-boring the cylinders, splicing chewed-through wiring, etc... finally got it put back together this week and am having trouble with the fuel delivery. The fuel pump does not turn on.
There is power to the double relay switch - terminal 86a checks out with the ignition switch on start, zeros out in "on" position , and AFM resistance checks out. The terminals at the fuel pump plug read zero volts unless the ignition is turned to "start" and the AFM is propped open - in which case it reads 7 - 8 volts. Don't know what to do---is there a way to test the pump to see if I need to replace it? Why would only 8 volts be making it to the terminals for the pump? Is this possibly a problem with the double relay switch? Any help would be greatly appreciated...I feel very close to bringing this one back from the dead. |
willimac |
Sep 15 2014, 12:24 PM
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#2
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Newbie Group: Members Posts: 14 Joined: 14-September 14 From: minnesota Member No.: 17,901 Region Association: None |
Thanks for the speedy responses. So I cleaned up the ground strap from the battery nto the chassis, and the ground connection by the distributor cap (brown wire from the double relay) and tried again., measuring the voltage at the connector to the fuel pump. Same result - fuel pump gets about 8 volts initially. I let it crank a bit longer (a few seconds) and the voltage it was receiving began to drop. got down to about 5.5 volts before I released the ingnition.
and here's another strange thing that makes no sense to me: with the voltmeter hooked up to the fuel pump connector and the ingition turned off, the meter measures between .125 and .140 volts of juice. when I disconnect the Positive terminal of the battery, the voltage slowly counts down to 0. I did install a new voltage regulator on the relay board, which looks quite different from the old one (not sure why I purchased it when I first started this project...Not sure whether the old one was good or not) Here's a pic of the new voltage regulator: confused about what is happening here, and would love some ideas re:troubleshooting where the problem lies. I'm on a steep learning curve when it comes to electrical components (IMG:style_emoticons/default/huh.gif) Thanks so much! |
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