Mmmm, Gooey

I figured I'd look at the fuel system. Based on my previous experience with the jet ski I figured it would be full of goo. At least it was cleaner than the ski. The basic setup was the same, though. It had a gas tank, oil tank, fuel pump, carburetor, and possibly an injection oil pump. I couldn't see past the other stuff to see if it had an oil pump. This might be a good candidate for premix, anyway.

I drained the fuel tank into a bowl. I got a couple cups of gummy gas. Then I removed the plastic fuel tank. While I scrubbed it out, Rob amused himself by burning the old gasoline. The fuel tank came clean pretty easily, although I didn't get it completely cleaned out. The fuel line was mostly clogged, though, so I replaced it with some generic fuel line.

If I hadn't already seen one like it on the jet ski, I would never have known what the fuel pump was. It's a diaphragm-type pump, that is powered by pressure pulses from the crankcase. It looked pretty dirty on the outside.

I removed the sump/drain plug. There was a lot of goo in there, so I pulled the pump apart. I was careful with the diaphragm, since I figured I would be using it again, and I got it out undamaged. The inside of the pump had more goo, as well as some hard crusty gray stuff. I dropped the pieces in a can of carburetor cleaner for an hour, and they came out clean. I reassembled the fuel pump, and tested it by blowing into the diaphragm hose. It worked just fine.

Now it's the cleanest thing on the scooter.

Update: I have since learned/realized that what I thought was a fuel pump was simply a vacuum-actuated fuel cutoff. Normally the diaphragm blocks the fuel flow, but when vacuum is applied the diaphragm moves, and allows fuel to flow. I'm guessing this is a safety feature, so that when you crash the scooter (or simply lay it on its side) the fuel doesn't all drain out. I didn't realize that it wasn't a fuel pump until some time after I wrote this, so you will see in the later chapters how this led me to some more wrong conclusions when trying to get the scooter started.