While I wait for DMC to get back to me with a solution for my pump (they are doing an excellent job by the way), I figured I could carry on working on the starting issue.
I Jury rigged the return pipe to the fuel pump, and tried starting again. Again she fired up for about a second then stalled. I got the wife to try cranking while I opened the fuel mix leaver but she just wouldn’t start.
At this point I remembered I had some engine starter spray, so I grabbed that. I’ve tried spraying this into the air intake before but I think it was evaporating before it got to the cylinders. This time I pulled the air hose off the idle motor and sprayed the ether down that hose.
The engine fired up, so I went to put the hose back on the idle motor, but as I did the engine sounded like it was going to stall again. I found I could directly control the engine by how much air I let down this pipe. I’m thinking at this stage the valve in the idle motor must be stuck closed, or it’s not getting the signal from the computer to open.
I wanted to re-charge the battery and check with DMC before continuing, but couldn’t resist taking a video first!