The engine is a 175HP XR2 from a Doral jet boat.
I have low compression on the 3 cylinders on the starboard side.
Port side is 130psi, 130psi, 130psi
Starboard is 20pse, 90psi, 20psi.
I took the head off and this is what the head gasket looks like:
Top cylinder 20psi
Middle cylinder 90psi...