hi all do you need to to change the bolt in the head when you change the gasket

which way up should the clutch slave cylinder go nipple at the top or at the bottom

my discovery300tdi has start bubble in the water with steam coming out of exhurst and spark come out with exhurst when you rev it up can anyone tell me want it is

my discovery300tdi has start bubble in the water with steam coming out of exhurst and spark come out with exhurst when you rev it up can anyone tell me want it is