Greetings from Michigan!
Knot salted is up in heated storage again. 2018 was good season with no issues, but not too many salmon either. We are not too serious, so it is always fun to try! No big trips this year.
Considering a three week cruise from Muskegon up to the North Channel next summer. I am wondering about my props as they have not been inspected since before we purchased KS.
No real problems in general cruising, the props sing nicely once in awhile when backing off throttles and when the water is colder, -indicating efficiency?- No vibrations or evident problems, but cannot get over 16-17kts and 2250 rpm most of the time, and it may be a power issue as the Perkins 6.354 turbos have 4300 hrs or so... with 10,000+ to go, I am not looking to do anything major with the engines, as there are no real issues other than stbd is a rough idler at 500-600 rpm (trolling speed) Have cracked the lines and replaced one injector with no change in performance. Both engines are smooth at all rpm under power, no smoke to speak of, start easy and never hesitate.
We are in fresh water, so the hull runs deeper and slower than she would in salt...
Also please don't get me wrong, 1050 to 1150 rpm and 7 kts depending on wind is where we are most happy and spend most of our time. This boat is made to get up and go when needed.
Boat new is 18,000 lbs dry.
Now is likely 21,000 lbs with gear and tools etc.. plus 250 gallons of fuel, so approx 23,000lbs
Bottom is clean as a whistle and smooth.
Max rated engine rpm is 2400, and max sustained cruise rpm is 2250 as I understand it. I can never get to 2400 and don't want to, but again, as I understand it, the boat should be able to do this if needed.
Trannys are velvets at 1.58:1
So, back to the props, a prop servicing facility took my specs verbally and said that my three blade 21x22 (cupping depth unknown to me) are correct for the boat. I have access to a set of 4 bladed 21x22 light cups and they stated that I would need to back them off to 21x21 or 21x21.5. Another place suggested backing my present three blades back to 21x21.
I am not looking to just increase rpm at given speeds, but want proper (pun) efficiency.
FlyWright, I bet you weigh in on this one..
I am not always online so will ping back when I can. Thanks All!