[Nasher]

Flip hi.

I am planning to run it for a test ride without the pump. Looking at it the float bowls are far enough down the tank that as long as I've got a 3/4 full tank I should be OK.

I'd not considered vapour lock, thanks for that, it's another avenue to consider.
It wasn't as warm Sunday afternoon as it has been on recent trips out where I've had no problems, but as you say it could still be related to the pump becoming a little tired.

Once again I'm stuffed for time in the garage until the weekend, so will have a play then.

Nasher.