Thanks guys .. have aleady had Ken (Skybeau) go over the whole machine a couple of years ago and he replaced and repinned connectors so I don't have reason to suspect them . Power supply was also rebuilt at that time . No coils lock on before the fuse blows but (and not sure if I mentioned it before) but just before the fuse blows many of the digits in the score displays go blank .. some in each display .. Buggered if I can see how that could be related to the circuit for the solenoids tho.

Because the problem is intermittent I think I will have to invest in a circuit breaker to help  make easier to track the fault down .. I am a bit lost as to where to start .. maybe replace all the coil diodes, though I think Ken already did that when he had it .

Appreciate the suggestions and please keep them coming as I need help with figuring this one out.

Also the CPU board and driver board are refurbished boards I bought from Ken.



Cheers
Dave