Probably only needs a new head gasket - Hopefully
Since the piston is already out of the cylinder - take the compression ring off the piston and put it 1" down into the cyl bore.
Square it up with the piston, Then using a feeler gauge check the PREG (piston ring end gap) measurement
Take PREG measurements in 3 spots top middle and bottom to check cyl bore
If the PREG is within specs ya know the cyl boar and rings are good and not the cause of low compression
Upon assembly, make sure the rings are clocked correctly
Since the piston is already out of the cylinder - take the compression ring off the piston and put it 1" down into the cyl bore.
Square it up with the piston, Then using a feeler gauge check the PREG (piston ring end gap) measurement
Take PREG measurements in 3 spots top middle and bottom to check cyl bore
If the PREG is within specs ya know the cyl boar and rings are good and not the cause of low compression
Upon assembly, make sure the rings are clocked correctly
