My V90 has massive oil consumption and oil is blowing from the filler cap so the whole engine is pressurised. There are no leaks anywhere else. The breather pipe isn't blocked so the oil is being burned. When the engine's running and you take off the breather pipe you can see the oil vapour being blown out.

I've just done a compression test and four of the cylinders are down on pressure the worst being cylinder 5. I added oil through the spark plug hole with a thin pipe so that oil ran down the cylinder walls around the piston in cylinder 5 and re-tested the pressure and it's jumped from 115 to 175 psi so I think the pistons and rings will have to come out.

Can anyone tell me if I can get the sump(pan) off with the engine in the car? If so I can then drop each piston in turn, examine the bores, and replace the pistons and rings from below if there's room.

Anyone know if this is possible? I don't really want to take the engine out if I can avoid it.

Thanks