My 2000 S25 has a Yanmar 2GM20F engine with a partial cowling between it and the cabin. I think this is a fairly common arrangement in sailboats this size with inboard engines. Is there any advantage to be gained from trying to upgrade the insulation and /or extend the cowling? I know we should be sailing and not motoring, but this season we have had a lot of windless days and we like to go out anyway, and the Seaward is an economical motor sailer at about a quart of diesel an hour.