Posted by farmer on 08/12/11 - 2:11 PM
#1
I just bought a 34 ft Defiance. Does anybody offers a power chip for the Yanmars to boost power a liitle before I get some much needed propeller tweeking done?
22 to 23 knts is the cruise speed at 2900 RPM. The motors easily top out at 3300 RPM. I want to get what I can out the motors before doing wheel work to get most out of everything.
Edited by Tom W Clark on 08/13/11 - 9:52 AM
Posted by John Fyke on 08/12/11 - 4:24 PM
#2
Is the boat and motors new? If so I would break it in before trying to get more out of the motors.
Posted by ShadBurke on 08/12/11 - 7:39 PM
#4
Are you able to achieve full RPM with the current set-up? A clean bottom can knock you down quiet a bit.
The 90% cruise #s look low to me but are dependent on how much weight you are pushing. By way of example, my 2000 35' Cabo Express with 3208 Cat 435hps cruises at 27knots and tops out at 31.5 knots. I have a very large tower and 115 + 45 gallon bait tanks in the cockpit.
You may want to check rest of running gear when you do work on the props. I upgraded my shafts to 2" after sheering off my workboat alloy 1 3/4"s in 60 hours.