87 F150 V8 won't start
05-06-2018, 01:19 PM
#11
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Test voltage across the fuel pump wires AT EACH TANK, and on the frame rail. If the pump doesn't run when there's 12V across it, it's dead.
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05-06-2018, 02:42 PM
#12
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I unplugged the connector for the frame rail fuel pump and tested for 12 volts and it has twelve volts.... but when I plug it back in the pump doesn’t run at all..... zero noise
05-06-2018, 09:43 PM
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Measure voltage with everything connected as normal.
05-07-2018, 11:45 AM
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Voltage is measured BETWEEN 2 points; not AT 1 point. The meter probes (a test light doesn't measure voltage) go on EACH pump motor wire.
Either backprobe the connectors, or pierce-probe the wires. For the frame pump, you can slide the rubber boots up from the pump body & see the bare metal terminals (which are often loose, in need of slight crimping to stay tight).
This is one type (my favorite) of pierce probe, but there are others:
Either backprobe the connectors, or pierce-probe the wires. For the frame pump, you can slide the rubber boots up from the pump body & see the bare metal terminals (which are often loose, in need of slight crimping to stay tight).
This is one type (my favorite) of pierce probe, but there are others:
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