Camray II won't fire/ignite?

Hello
Just hoping someone can give me some clue. Have a Boulter Camray II which I did the usual, ran out of oil in the spring. Now have oil so was expecting the usual - having to use the reset button and possibly bleed it. Have done all this but still can't get it to work. When I press the red reset button it starts off ok, then the next sound it makes is a different sound it usually makes - slightly tinny/metallic then it just cuts out and goes back to lockout without trying to fire up. Also last time we used it, it wasn't turning off by the wall-mounted timer control - have since replaced this.