Fuel Leaks

The motorcycle origins of parts of the 700 design pop up here and there. The fuel system is a case in point.

The fuel tank is mounted in the front luggage bay and is slightly above engine height. Yet there is a fuel pump drive by the engine as the float chamber is about or higher than the tank.

Yet, there is a fuel tap as used on gravity feed systems. The tap has three positions, off, on and reserve. Although how the reserve function works was unclear as there is one pipe in and out of the tap, the trick is that the tap mounts directly to the tank and the reserve position allows petrol in the bottom of the tank to flow through the tap. The tap is, largely, redundant, especially in this case as the engine seems to operate equally well regardless of the tap position!

Nonetheless, the roadworthy inspection claimed the tap to be be leaking.

I could find no leak, but I have had the tap in the ON position since starting the trip to the roadworthy. It was in the OFF position as delivered, driving itself off the transporter and a little bit outside my house. So maybe it only leaks when turned OFF.

It has remained dry at all times since, so no further action required.

The other fuel leak, reported as being from the fuel pump diaphragm, was actually from the outlet fitting on the pump. A short section of brass pipe is meant to be a push fit into the pump housing with the rubber hose clamping to that pipe. But the pipe pulls out easily by hand. Hence the slight leak.

This shows the short section of brass pipe still firmly held in the rubber hose, and the hole in the pump housing where the brass pipe should be.

A good smear of epoxy glue has secured the pipe and fixed the leak.

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