Calling on MD 7/11/17 know it alls

[Patrick of M]

I have an md17 that had a little water in the oil. Probably manifold, or water pump">raw water pump. I have a little time before the spring and it occurs to me, re sealing the bores might be proactive. I want to pull the blocks anyway to check the piston rings etc. This engine will be converted to fresh water cooling, so if I pull the sleeves I can clean up the cooling jacket. My question...are sleeves reusable? Mine look fine and I have spares...

[skipperpete]

I’m far from being the guy you need to answer your question about the cylinders BUT I have had experience with the injector sleeves, these can and will leak, in your case salt water. Replace the orings or at the very least pressure test the heads and sleeves.

[DougR]

If the cylinder liners (sleeves) are in good condition, there is no reason they couldn’t be reused. And, when the liners are out of the water jacket you will be able to clean up the inside of the water side of the water jacket to start fresh with your freshwater cooling.

I rather doubt , however, that the small amount of water you are getting in the oil is coming from the cylinder O rings. There is an O ring sealing the water jacket and the liner at the top of the water jacket ( under the liner flange), another O ring at the bottom of the liner where it protrudes from the water jacket, and a third O ring in the crankcase where the liner extends down into the crankcase. Think it’s unlikely the water is getting out of the water jacket and then back down into the crankcase past the lower O ring.

When you pull the water jacket and liner off the crankcase, keep track of the shims located between the waterjacket and crankcase, and mark each waterjacket and piston so they can go back in the same location. The shims control the compression ratio of each cylinder, and need to be in their original position or you will need to readjust.