An engine is such regardless. I too have not seen a hydraulic lifter boat engine. Specific parts that do work are rods, block, valve lifters, rockers etc. The price at 6K is to high, just someone dreaming. Normal price is between 1500 and 3500, or should be. I recently bought one for 2K and actualy had both engines bought for 3K, untill I found one had water in 3 cylinders. The nice thing about these engines are that these are usually well maintained and have run times of anywhere from 1k to 2k hours, and can be found in perfect standard bore at times.