Thanks Ron,

Propane level is fine, EGT is reading correctly, Pump Start is at Auto+3 but the engine converts from gas to kero quite easily, Pump ramp is at 007.

I should have mentioned that the engine is a Mk3.

The first part of the start is generally fine. The problems occur at about half way during the start and even after the starter motor has been disengaged. Once running it seems to be fine.

The engine was fine until it was removed from a model and left unused for a while. I'm wondering if something (the pump or something inside the engine) has become gunged up somewhere. It just seems a bit odd that the problems only happen during the start cycle and not even at the beginning of the start.

Last time out I sprayed a bit of lube into the pump motor can just in case but I only had one start due to the weather so need to try again when it has had time to soak in. I can get the engine running at the moment so can just about live with it. If it gets any worse then I'll have to take it to the Wren factory for them to have a look at.