Ashes to Ashes, Rust to Rust
After much hammering, disassembling, cursing and cleaning, the engine problems have been diagnosed.
Here is one of the starboard exhaust risers:
Note the rust and general state of distress.
Basically, these cool the outgoing exhaust by jacketing it in seawater. On one side (the rectangular side) you can see two sets of inputs, a central square where the exhaust runs, and an outside chamber surrounding that where the seawater flows. They stay in separate chambers until they pass the top of the rise, where they then mix on the downside and exit together via the circular port on the other side, and then travel together through the muffler and out the rear of the boat. In this case, the wall separating the exhaust from the coolant had rusted out, allowing water to flow back through the exhaust shaft and into the manifold, and from there into the head and cylinders. This is obviously bad, since fuel and water do not mix nicely.
Both manifolds and risers on the starboard side required replacement, and the heads needed some machine work to clean them back up. While all of this was going on, we discovered a broken valve stem which also needed replacement. Additionally (note a theme here?) some moron in the past had used silicone on top of the head gaskets, which made a giant mess of things and needed to be cleaned off of all the surfaces before a new gasket could be put down. On top of all of that, the alternator bearings needed replacement, and the impeller on the water pump seized up and needed to be replaced as well. This doesn't even get into crummy hoses that will probably need replacement in the future, or myriad other small issues like mismatched spark plugs.
Once we (and by "we" I mean Kory, the mechanic) got everything reassembled, a gasket on the oil filter popped and we had a nasty little oil slick in the bilge. That was some nice icing on the cake with that engine, but it got repaired.
Thankfully the port side was much easier. The starter had shorted out on that side, and after a trip to the motor shop in Ballard it's as good as new. The only other major issue on that side was again a bad impeller on the water pump, and a missing spring in the distributor cap. It's got the same hose woes as the starboard side (and probably a leaky gasket on the coolant reservoir?) but it started right up after the starter was repaired and things look good on that side.
Haul-out and survey are on Monday, and barring disaster there the boat will hopefully be in new hands shortly thereafter!