Thank you for the help.
I will have a mechanic give it a thorough check asap. I can get 3400 rpm and I cruise at 2600 to 2800 in flat water at 5.6 to 5.8 knots. (I have a bracket for my 4 hp Yamaha outboard on the stern and can hit 4.1 knots in flat calm -- the hull is easily pushed.) At 2500 I do 5.5 knots. It is the waves that REALLY slow me down. I will check the fuel supply and linkage, but I have had the tank out, put in inspection plates and replaced all plumbing, fuel pump, etc. Also completely rewired engine, panel, and replaced harness last winter. Yes, and hauled, cleaned, new injectors, checked valve clearances and lift pump July 2010....thanks Tim. I have had the Max Prop for nine years and it took a number of tweeks to get the pitch right. I think I'm there on that one. The exhaust I checked last summer, there is no muffler to create back pressure. All your comments make me think that my problem is likely lost compression and, given the knots Loren gets, I think the 29 hp Yanmar would be ample. I will let you know what the mechanic says. Most to all of my summer cruising is done from Desolation Sound north in fjords among islands where motoring accounts for 60 to 80% of travel time. The wind is either on your nose or tail, or not at all. The engine only has 2100 hours, but the PO admitted to motor negligence
Duncan.