Many thanksfor your help. We have at last found the problem.

Briefly. Thr carb rubbers were replaced 4 weeks prior to the increase in temperature of 20*. Whilst once more trying to find what was wrong the resident mechanic decided to have a look at the carb rubbers to see if they had seated propley ...

Hi Guys. I'm not very good at driving computers or forums but I'll give anything a bash as I want some help!
My C42 with 912S engine has decided it wants to run 20* hotter than it's counterparts but still within it's limits, which is okay at the moment but when the weather gets hotter it could pose ...