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Bad fuel pump and effects

Started by Bob C, September 06, 2022, 03:24:01 PM

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Bob C

    From trying to get my 1992 FJ to start well, I found the problem. The electric fuel pump, aftermarket , I think, was the culprit. There is a small spring in the movable lower points arm which has a plastic ( I think ) foot on each end of it . This spring gives the snap to the points movement. The foot nearest the points was split / broken, and this made the spring hold the points shut all the time. So, on putting the switch "on" , a little "cluck" was heard, the piston/ diaphram going down, and staying there. Normally this would give no fuel to the engine. Second Problem: one of the check valves was leaking / broken. This is how the bike still worked a bit ,as it was leaking a small amount of gas to the carbs , all the time, even when parked. This made the fuel levels in the carbs go too high after a few days or so, and was just too rich a set-up to start . The person I bought the bike from used to lift the back of the gas tank up and shut the outlet valve , if he was parking it for more than a day or two , a lot of work every time, and he still had fun starting it even after a day or two . I am buying a new pump for my bike, now, and may install an  in-line valve in the line to the carbs as an extra safety. All this mess because of a defective pump !

Bob C

  One other point is that the FJ1100 , with no fuel pump, uses a vacuum operated fuel tap to shut the gas off when the engine is not running . So, the fuel pump bikes rely on the pump to stop the gas pressure to the carbs when not running