Aruna has an interesting raw water system. There are two 2" inlets in the port stern area of the engine room. Both have motor-driven valves to open and close them. One is labeled engine, the other for air conditioning. There are switches and indicator lights at both the main pilot house driving station, and the flybridge driving station.
The lights do not work as a result of the limit switches at the valves being old and unreliable.
After these come into the boat, they go into a series of pipes that can be changed/configured with valves. Right now, I have both 2" inlets cross connected so they both feed the following:
- Main raw water strainer - this then goes to a series of valves for the main engine hydraulic and oil cooler loop, generator, and raw water washdown
- AC raw water strainer
- Watermaker raw water strainer
I always have both open all of the time, unless I’m doing maintenance. The crossover valve between the two appears to have been added later on. I could use one for the engines, and one for AC/watermaker, but having them crossed over means less likelihood of one not working.
The biggest issues are:
- Main engine strainer is not far enough below the waterline. If I don’t shut ALL of the valves everywhere, and I take the strainer top off, I have to re-prime the system which takes a lot of time and effort.
- Electric valve system is needlessly complex. At some point the motors will fail completely.
I’m wondering about a few things for other Kristen owners:
- Do you have a similar system?
- Does your strainer have priming issues?
I plan on removing the electric motors, limit switches, etc. and just using the remaining pieces to open/close the valves when needed.
However, I would like to redesign where the strainer is so that I don’t have a prime problem.
