I have been trying to get this old Rover going and I am sure I did have it running when I first brought it home. However, I got around to having a look at it after a couple of weeks and could not get it to start. Spark and compression were fine and if I squirted some fuel into it, it would run until the prime ran out. I looked into the fuel tank and it had enough fuel for testing so I thought carburettor. I cleaned the carby but same thing. Changed the carby and same thing. It finally dawned on me to check the fuel. It looks like water. I wish I had just had the brains to test that first instead of all the rigmarole I went through.
I think it originally started because the carburettor initially must have had better fuel than what was in the tank which had become contaminated with water. That's the theory anyway.