Hans-Erik, Bob is correct in questioning the condition of the bottom of your boat - and also of the prop. You haven't said where you sail, but if barnacles are a possibility there I'd get a diver to look at the bottom of the boat.
The proper diameter and pitch prop for your boat (and a clean bottom) should let you get approximately hull speed (somewhere in the 6.5 KT range?) at about 80% of max RPM. My friend's 29-2 with a 2GMF and a 14x9 2 blade prop gave us 6.3 @ 2400 RPM and 6.5-6.7 at 3000 RPM on the long motor back from a race this past weekend. Rick Brass Washington, NC -----Original Message----- From: CnC-List [mailto:[email protected]] On Behalf Of robert via CnC-List Sent: Wednesday, June 24, 2015 8:56 AM To: [email protected] Cc: robert; Hans-Erik Andersen Subject: Stus-List Cruising/max speed for 1980 C&C 32 Hans-Erik: We have the same engine.....our 32 has a fixed 2 blade prop (Michigan) .......from your numbers provided, your boat is not performing the same as ours. I can 't be precise, but our boat is approx. 1 knot faster at the rpm's you mentioned (GPS speed, not Signet knot meter). What's the condition of the bottom of your boat? Rob Abbott AZURA C&C 32 - 84 Halifax, N.S. On 2015-06-24 1:54 AM, Hans-Erik Andersen via CnC-List wrote: > I've recently purchased a 1980 C&C 32 with a yanmar 2GM20F 18 hp diesel. We're having some propeller/power issues, and I'm wondering if anyone here would have idea of what the approx. cruising/max speed should be for this boat and engine. I'getting 5.9 kts at full throttle (3400 rpm) and 5.3 kts knots at 2800 rpm. Is this reasonable, or cause for concern? > > Thanks! > > Sent from my iPad > _______________________________________________ > > Email address: > [email protected] > To change your list preferences, including unsubscribing -- go to the bottom of page at: > http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com > _______________________________________________ Email address: [email protected] To change your list preferences, including unsubscribing -- go to the bottom of page at: http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com _______________________________________________ Email address: [email protected] To change your list preferences, including unsubscribing -- go to the bottom of page at: http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com
