So - I have twin 427's on my 1973 Hatteras 43' Double Cabin. Port is running fine. Starboard is in trouble.

Took her out for her maiden voyage this year (we bought her in the Spring) and the Starboard engine was running rough and stalling. Went to gas up - I though she may be out of gas or running on very old fuel. I thought some new fresh gas would let her get back to a smooth run. It did not.

She sputtered and spit - felt like she was running on 6 of the 8 cylinders. Took her back in to the slip. She stalled out 2-3 more times and didn't want to start in the slip. i figured I would let her rest and called it a day.

Next day - check the points (double points) - only 1 set sparking. Change the gas filter & check the water separator. Gas is dirty but no water. She still won't start, even with some starting fluid sprayed in. clean up the points but no love.

Next day - marina mechanic (Bob has worked on her for the past 30 years) changes the points and pulls the plugs - Finds water on 7 of the 8 plugs. Here is where the trouble begins! He leaves the plugs out and sprays cylinder foam / oil in (which I fear has allowed the cylinders to rust a little since the plugs were out).

Next day - the pistons are moving Very Tight - very slow crank from the Starter. This is the first time we experience a slow crank.

And next - the Starter goes out to be rebuilt - full new armature - rather "chewed up".

Starter back in and the engine is still rotating Very Stiff - with the plugs out.

I spray some Marvels Mystery Oil in the plug holes to coat the cylinders ... and some of the foaming cylinder lube. Plugs still out. After 24 hrs - Still a very tight turn and slow crank. Not wanting to burn out the starter again .. I stop. Note the turning is difficult with a breaker bar as well as with the starter.

So - mechanic pulls off the intake manifold and sends it to machine shop to see if we have any cracks - source of water in the cylinders. Waiting to hear from machine shop.

Still a tight turn - figure we will pull the head and hone / deglaze the cylinders (4" hone - Correct?). Will keep very well lubed with Mystery or honing oil.

If crack or flaw in intake manifold - that should tell me how water is getting into the cylinders .. if not .. I am thinking of looking at exhaust manidolf / system next.

Any thoughts on source of water? Freeing up the cylinders / Pistons?