I find that the engine compartment on my W32 runs 25-35 degrees F warmer inside than the outside ambient temperature when cruising at 1800 RPM. That's hard on battery life. Years ago I bought some gel cells, they were ruined the very first day in that compartment. It also cooks the soles of my feet on the cockpit floor.
Mine is perhaps hotter than most because I have two jumbo size lazarette compartments under the seats port and starboard. They wall off perhaps 50% of the volume of the engine compartment, greatly reducing the remaining volume. In that volume is the engine and house batteries.
I'm thinking about adding engine compartment ventilation, with an air inlet from the cabin, an exhaust somewhere aft in the cockpit (but forward of the aft lazarette bulkhead), and a fan. I'm concerned with
- Letting noise into the cabin
- Letting water into the compartment via the exhaust
- Wasting my time with a vent system that doesn't provide enough air flow to make a difference.
Experience and advice from other W32 owners will be appreciated.