2.5 banana engine

[B4ndit]

hi,
i need help with my engine it runs great but after about 2 miles it blows the oil filler cap off anyone got any ideas on what could be causing this thanks in advance for any help
Terry

[dumper]

Check if the brether pipe is clogged and the cap and not over full of oil also maybe egr valve faulty have you cleaned the inlet manifold out they get well clogged up and worst case scenario cracked piston or worn out piston rings/ worn bore
but start with the simple things first

[B4ndit]

Thanks for the reply it's just had new rings and valve guide oil seals and new gaskets right through will check the breather system and manifold over the weekend, was wondering if it could be the oil filler cap at fault?