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90 K75RT fuel pump

madmatt

gotgas-touring nogas-lost
installed a new fuel pump and related parts (in the tank), it worked when out of the tank & "hot wired", nothing when installed. the K will sputter with starting fluid so it wants to start but it's not getting fuel. when I removed the old pump, there was a piece fuel line about 2 inches long attached to the decomposing fuel pump screen at the bottom of the pump, is it supposed to be attached to the metal fuel line inside the tank near the top that was just hanging there in mid air with nothing attached or is that a "breather" line and the line on the screen is just supposed to be 2 inches long to keep it above the crude at the bottom of the tank? I did attach fuel line from the fuel pump screen to that metal line, could that have created a vacuum that could have stopped the fuel pump? the pump is attached correctly to the fuel filter and then to the metal fuel line at the bottom of the tank. fuse is good. I'm open to suggestions, thanks. the K has not been started for some 24-30 months with little fuel (pumped out & cleaned) in it. it was not prepared for long term storage.:banghead
 
Question one is have you verified that the fuel pump, as installed, is actually turning on and running?

Try just a short stab of the starter button, not long enough to start the engine. You should hear the pump run for a few seconds. Open the fuel cap. This helps the ability to hear the pump.

If the pump runs and you are not getting fuel it sounds like a plumbing issue. If you don't hear it run you have an electrical issue.

If the pump is not coming on the connector at the pigtail from the tank is the prime suspect.

Also somewhere down the list is the possibility that you have fuel pressure but no injector openings. Since this is unrelated to installing a fuel pump I doubt this, but might keep it in the back of my mind.

To do a fuel pressure test you need to "T" into a fuel line at the fuel rail.
 
Try taking the filler cap off and connect the leads from your voltmeter to the leads on the pump. Then hit the starter, like Paul suggested. This will tell if power is getting all the way to the pump or not. If you don't get power, the connector to the tank is one area that can be a problem, the other is the plate on the bottom of the tank where the wires pass into the tank.




:dance:dance:dance
 
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