Bart F-350
Full Access Member
well, My truck is old in years, but (almost) new in mileage, 10234 Mi.
I did test the resistance in the fuel circuit, I measured AFTER the hose, so just before the fuel enters the lift pump, and I had ZERO resistance (or vacuum) at stationary, and non when I had more rev's, I had no Rpm gage when working under the hood, so helas.
Then I measured at the schrader valve, zero pression while stationary, and when I was revving the zero "pression" changed into 10 and more Inches Hg vacuum.
Then I measured again at the connection where the brass valve connects to the fuel retour circuit, that's the after filter circuit,
had a pressure of 2,5 - 2.8 Psig .
running the engine up to 3000 Rpm for two minutes, pressure dropped to -10 Inch/Hg vac.
Then released pedal, Rpm's back to stationary, pressure came up, but did not depass 2 Psig.
I did test the resistance in the fuel circuit, I measured AFTER the hose, so just before the fuel enters the lift pump, and I had ZERO resistance (or vacuum) at stationary, and non when I had more rev's, I had no Rpm gage when working under the hood, so helas.
Then I measured at the schrader valve, zero pression while stationary, and when I was revving the zero "pression" changed into 10 and more Inches Hg vacuum.
Then I measured again at the connection where the brass valve connects to the fuel retour circuit, that's the after filter circuit,
had a pressure of 2,5 - 2.8 Psig .
running the engine up to 3000 Rpm for two minutes, pressure dropped to -10 Inch/Hg vac.
Then released pedal, Rpm's back to stationary, pressure came up, but did not depass 2 Psig.
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