Model: 15003-031185 380 hours (100 hours in saltwater in the last 4 years)
Problems:
1. Initial problem was motor was peeing very little water (drops) out of the side while at any rpm, in gear or out of gear. Thermostats are working properly, (already checked on the stove and they open fine). The poppet (pressure) valve on the starbord side below the bottom cylinder is working as it should. On both cylinder heads there is a water tube going from the bottom to the top. After taking off the tubes and connecting the hose with engine off, water flows from top and bottom on the starbord side but only flows out of the top hole on the port side. The bottom hole is completely dry, not a drop of water. Also, the bottom port side cylinder is red hot to the touch, more than any of the others. So the only thing to do is pull the head off. On to problem 2.
2. After pulling the port cyl head off there is a milky water/oil/fuel mix in all three cylinders. Some normal saltwater blockage is in the water passages but nothing major. Top and middle cylinders have minor rust (fuzzy to the touch) along the cyl walls. Should be able to get off with light sanding with sandpaper or scotchbrite pad. The bottom cyl (the one that was hot) looks good; no rust and oiled. The top cyl head is wet and full of carbon and the bottom is white with almost no carbon buildup. I thought it was because of it getting so hot but one mechanic seems to think its from water in the bottom cyl blasting the carbon away. Being curious I looked at the 3 starbord sparks plugs only to find that they were all covered in the milky muck of water/oil/gas. There is no water in the gas. Last 6 months the motor has only been run every weekend on fresh 90 oct non ethonal fuel from a 5 gal tank through a new water separator and new fuel lines. The mechanic thinks water is getting to the cylinders from the exhaust ports somehow.
3. While idling in the water I pulled each of the plug wires one by one. Only 3 of the plugs I pulled made the motor lower rpms and change sound.
Questions:
1. Anybody have any ideas why the engine isn?t peeing water? (besides a blockage in the starbord water passage that I cant see)
2. Why is there water in ALL 6 cylinders?
3. Why do only 3 cyls change the rpms? Is it possible there is too much water in the 3 cyls for them to have a spark?
4. Should I dig deeper into the engine looking for an answer or clean what I can, bolt back together, run the motor and check spark plugs for signs of water?
5. Can I do a compression test on the starboard 3 cylinders with the port head off?
Anybody that has an idea feel free to chime in here. This motor isn?t too common and not many people know how to work on them so I need all the help I can get at this point. See pics