It sounds like it is overheating if it will not restart when you turn off and back on again.
This could be down to poor circulation with a faulty pump or a sludged up system
Or it could be down to a faulty thermostat, but your water would be red hot and the overheat stat working correctly
Or it could be a faulty overheat thermostat tripping too low
Try turning your boiler temperature down and see if it stays on longer?
problem is it wont fire up then two days later i will switch it on as a last effort and it fires up its queer
When it does not fire up, does it make any attempt?
Does the fan run at all?
no the fan does not run and its as if the the boiler wants to fire but does not make that whirling sound before it fires into action. it will sit like this for two days and then for some reason when you try it, it will make the whirling sound, then its as if thats the fan coming on and it then fires up with no problem.
Can you take the case off and see if the fan is free or is stiff?
no its running free