Dudley flush problem

[rsk289]

I have a Dudley concealed cistern fitted with an Electroflo flush using battery power. The first 'blue' (long) flush of the day, when it's been inactive during the night, often doesn't work properly - the blue light comes on, the motor runs - then there's a 'thump' and everything stops. If I wait until the red light goes out and try again it works fine.
I've replaced the green and white flush valve complete, the electronic control box and, in desperation, the actual electronic sensor with the LEDs. No change. Has anyone experienced this - could it be a problem with one of the two air pipes, or the inlet float valve? The 'green' flush works fine every time. Is there a guide somewhere on how to set the adjustments up on these? I know they can be adjusted for more water or less, but I don't know if I need more or less.

 

[rpm]

https://www.google.co.uk/url?sa=t&r...ructions.pdf&usg=AOvVaw2es5mtRhiJoyg6Gklao2kf

12 Troubleshooting. Not a lot there tbh but it does tell you about increasing or degreasing the pump run time.
Don`t thank me, thank Google

 

[rsk289]

Thanks, that's helpful - but when it fails the pump motor runs for a short time (at the normal speed, but for a shorter time than usual). Whilst it's running there's a 'thump' and it just stops dead. The red LED comes on and stays on for the normal time, even though the (still full) cistern isn't filling. I changed the components listed above, one at a time, and none made any difference. Is there another component that might be causing this? Could it be the inlet float valve, which is the only thing I haven't changed?

 

[rpm]

If it`s not covered in the link I posted then I know as much as you tbh.
Have you tried ringing Dudley?