Ok guys. Trying to solve a weird mystery. I had the carb rebuilt for my Daihatsu Midget what has the same motor as the Hijet. I put it all back together the same way it came apart. I took good photos before so I could make sure all the lines went where they were supposed to. Because the truck was sitting so long, I wanted to prime the fuel pump and make sure the fuel was getting to the carb, so I pulled the fuel line that went from the fuel pump to the carb. The other 2 fuel lines (fuel tank intake and return line) I left hooked up. I put the carb fuel line into a bottle so when the fuel made it that far, it would go in the bottle instead of making a mess. That's when things started getting weird. Fuel started coming into the bottle (the line that feeds the carb) as it was supposed to, so I was going to quit cranking the starter....but then all of a sudden it started sputtering and begins to idle!!!! It ran for about 5 seconds, and then died. I hooked the fuel line back to the carb and expected it to start running, but it would start anymore. Not even sputter. What the heck is going on. How is the truck running when the fuel line to the carb is disconnected?!?!?:frustration: and why won't it run now? Keep in mind this was a FRESH rebuilt carb with NO fuel in it. Am I missing something? Is there another line that goes into the carb that delivers fuel that I don't know about? HELP!!!
the electric solenoid on the side of the carb may not be allowing fuel into the carb...it prob. ran a second or 2 on the fuel left in the float bowl
What Solenoid? Can you explain where? What tells the solenoid to let fuel in or not? Is there anything I can check to fix... There was NO fuel in the carb. It was BONE dry 100%. Is there another fuel source going to the carb?
it could have sputtered and run a bit on residual fuel in the intake manifold ? not sure... the solenoid is under and left of the green/black vacuum valve in your last pic. it gets a signal to open from the ignition switch....unscrew it and turn the ignition on and of and see if it is moving
I'm still not sure, as the truck sat for at least a month, and the bone dry carb was hooked up from there. I doubt there would have been any fuel left after a month. And if so, it would have started first thing when I tried, not after cranking it for 2 minutes to prime the fuel pump. I'm still thinking something is hooked up wrong. Does it appear that my fuel pump is hooked up proper? Can do. Thanks! I'll keep you posted,
It was most likely running on residual from fumes of fuel, oil, and/or cleaners. Liquid fuel will not burn only the fumes from the liquid do. To test this take a very small paper cup of gas and light it with a LONG match or lighter watch how only the fumes off of the top will burn and not the entire contents of liquid. Many liquids or fumes there of are also highly flammable hence solving the "mystery" combustion.
The solution is simple:Fuel vapuur recovery canister. I think in USA it is used since '70s... If the valve opens (I think it works with vacuum lines) and the canister is full of fuel, the opening of the canister allows fuel vapours to enter in the engine...then engine starts. Engine has no magic things into it...