massey 1260 compact

hi i have a fuel problem with my massey think it may be pump or cut off how can i check this before i send the pump away to be looked at can i check the fuel kill it appears to be working but cant be 100% if its opening help!!!!! fuel only just passing through the pump to injectors with little or no pressure any help were this fuel cut off is concerned would be great thanks wulber:banghead3:banghead3