I have a 10 yr. old twin Volvo 5.0 GXi duoprop setup with water intrusion in the center 4 cylinders of both engines over the past 6-7 years. I have 1. replaced riser gaskets with no resolution; 2. Replaced risers, manifolds, refurbished the heads with no fix; replaced riser gaskets (the metal ones recommended) with original material gaskets with no fix. No water in the oil. Compression is on average, ok, but not great after all this. The work was performed by a Volvo dealer. Any suggestions?
