Oil light and ayc light

[Steevo]

Since fitting my new engine with the balance shaft removal kit on it I seem to have the oil light on when car idles at 1000 as soon as the pedel is touched it goes out if the car ticks over higher tHan 1000 it stays off. Also since refitting my engine I have the ayc light on this was never on before I am just wondering what may have caused this I have fresh oil in the ayc and all was fine before removing and refitting the engine any help would be gratefully received I'm also after an alloy radiator if anyone knows of one
thanks steevo