Faulty pilot burner?

I have a johnson & starley j25 warm air heating system but am having problems with the pilot burner. It lights, fires up, expels warm air for about 30 mins then cuts out, and i have to keep relighting the pilot burner. I need 2 things.......a good local service engineer in Birmingham, and an online user manual, as when i bought this house there wasn`t any paperwork for the heating, at least no user guide. Any help would be greatly appreciated.