Lifter Valley Inspection
A bit of a Mystery Here
MerCruiser lifter valley lifter Inspection
So to get here required removal of a lot of items. This turned out to be a lot more complicated than just “Remove the distributer and Intake”.
So the mystery deepens. A quick inspection of the Mercruiser 5.0 MPI lifter valley indicates that there is no obvious sign of cracking. Additionally, There is a lot of rust on the intake ports on the Starboard head.
So there may be a crack in the rear water jacket. Consequently, the engine would ingest water into the crank case. The Starboard intake runners in cylinders six and eight show signs of water ingestion, but very little rust in the lifter valley. To see the how we got to this point.
Mercury 5.0 MPI Intake Runners and Water Jackets
Head and Related Ports
The Ports in the heads that are highlighted red are coolant passages or water jackets. Be aware, the water jackets are at the front and rear of the heads on both sides. Lastly, The Rear left port (Starboard) was the one that we found oil and water.
The Ports in the heads that are highlighted white are the intake runners. As is as stated above a lot of rust in the rear intake ports on the starboard side.
At this point I’m fairly into the motor, and there is not a real obvious sign of where water is coming from. As a result, I will pull the Starboard Head and see what is going on on that side. Now if there is nothing obvious, I will bolt it back on and pull the motor. It probably a good idea regardless of what I find. Additionally, I do not want to fix this minimally, just to spin a bearing and go through the whole process of dissembling and removing the motor. Stay tuned!