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Peter & Judy



Joined: 03 Dec 2014
Posts: 570
City/Region: Olds
State or Province: AB
C-Dory Year: 2005
C-Dory Model: 22 Cruiser
Vessel Name: Mistaya
Photos: Mistaya
PostPosted: Sat Apr 30, 2022 6:25 pm    Post subject: Reply with quote

I too have a 2005 22' Cruiser that was repowered with a Honda 90HP after the original Honda 75 was removed.

I tend to travel with a fairly heavy load and the 90HP is more than adequate for me and my needs. I think you have to consider your boating style and needs as it is easy to overpower which in the end might prove more expensive than you really need.

My boating style is long distance cruising most of which I do at about 6 knots and once in a while I will go up on plane at 12-14 knots. I have never had my boat up to WOT and I am not sure I ever will have the need to. I like the fact that I can get to a higher speed when necessary, but mostly I like to look at the scenery and relax. Had I wanted a high powered, high speed boat, I don't think that I would have bought a C-Dory.

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Peter & Judy Haase
Buffalo Horn Ranch

HMCB Mistaya
"Mistaya" (Grizzly Bear in Cree)
HMCB (Her Majesties Cute Boat)
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thataway



Joined: 02 Nov 2003
Posts: 21469
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Sat Apr 30, 2022 7:09 pm    Post subject: Reply with quote

That speed is excellent for a 70 HP motor!
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Bob Austin
Thataway
Thataway (Ex Seaweed) 2007 25 C Dory May 2018 to Oct. 2021
Thisaway 2006 22' CDory November 2011 to May 2018
Caracal 18 140 Suzuki 2007 to present
Thataway TomCat 255 150 Suzukis June 2006 thru August 2011
C Pelican; 1992, 22 Cruiser, 2002 thru 2006
Frequent Sea; 2003 C D 25, 2007 thru 2009
KA6PKB
Home port: Pensacola FL
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Foggy



Joined: 01 Aug 2013
Posts: 1580
City/Region: Traverse City; Northern Lake Michigan
State or Province: MI
C-Dory Year: 2014
C-Dory Model: 26 Venture
Vessel Name: Boatless in Boating Paradise
Photos: W B Nod
PostPosted: Tue May 03, 2022 10:03 am    Post subject: Reply with quote

Peter & Judy wrote:

I tend to travel with a fairly heavy load and the 90HP is more than adequate for me and ......
My boating style is long distance cruising most of which I do at about 6 knots and once in a while I will go up on plane at 12-14 knots. I have never had my boat up to WOT and I am not sure I ever will have the need to.


Continuous suboptimal engine rpm (aka "putt-putting") ages engine life.

Modern outboard engines are designed to run WOT. Babying, starting at break-in
avoiding short WOT, can fail to seat your piston rings. Thereafter, occasional WOT
is actually good for the engine. Constant WOT makes no sense.

The goal is to find your engine's "sweet spot" for the long cruises. That sweet spot
can be somewhat customized to your usual boat load by selecting the best engine
power/propeller combo from the start.

Aye.

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Keep an open mind just enough to not let your brain fall out.
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Peter & Judy



Joined: 03 Dec 2014
Posts: 570
City/Region: Olds
State or Province: AB
C-Dory Year: 2005
C-Dory Model: 22 Cruiser
Vessel Name: Mistaya
Photos: Mistaya
PostPosted: Tue May 03, 2022 10:41 am    Post subject: Reply with quote

Quote:
The goal is to find your engine's "sweet spot" for the long cruises. That sweet spot
can be somewhat customized to your usual boat load by selecting the best engine
power/propeller combo from the start.


There are two sweet spots for my boat and my boating style. I find that I cruise mostly at 2400 RPM (6 Knots) and 4400 RPM (12-14 knots). My typical cruise is 10 - 14 days long, so heavily loaded. This speed combo gives me the fuel efficiency that I want and the speeds that I enjoy. I boat primarily off Vancouver Island and I want to keep my speeds to a comfortable and safe level. In these waters there is a lot of logging activity and you need to keep a sharp eye out for floating logs and deadheads. I have had a few close calls, especially when the water is choppy and the logs are hiding amongst the waves. WOT is just too fast for my liking and safety.
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thataway



Joined: 02 Nov 2003
Posts: 21469
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Tue May 03, 2022 1:30 pm    Post subject: Reply with quote

I recently purchased a new Suzuki 2.5 hp 4 stroke OB.

Break in instructions for all Suzuki are:
1). Idle in gear for 15 minutes. (Always idle for 5 minutes before applying higher throttle.)
"Running at high speed without sufficient warmup may cause severe engine dam-age such as piston seizure. Always allow sufficient idling time (5 minutes) for the engine to warm-up before running at high speed". You should avoid running at one constant speed during the break-in peroid--vary the throttle.

2). Then for the first 2 hours no more than half throttle (3,000 RPM), next Hour up to 3/4 throttle ( 4,000 RPM),

3). The next 7 hours you may run up to full throttle for no more than 5minutes.

Running continuously at full throttle for more than 5 minutes at a time during the last 7 hours of break-in operation may cause severe engine damage such as seizure. During the last 7 hours of break in operation, do not operate at wide open throttle for more than 5 minutes at a time.

Honda for the first hour, 15 minutes at trolling speed, then "Running continu:usly at full throttle for more than 5 minutes at a time during the last 7 hours of break-in operation may cause severe engine damage such as seizure. During the last 7 hours of break-in operation, do not operate at wide open throttle for more than 5 minutes at a time."
"Running continuously at full throttle for more than 5 minutes at a time during the last 7 hours of break-in operation may cause severe engine damage such as seizure. During the last 7 hours of break-in operation, do not operate at wide open throttle for more than 5 minutes at a time."

Mercury 90 HP: 1. For the first hour of operation, run the engine at varied throttle settings not exceeding 3500 RPM or at approximately half throttle.

2. For the second hour of operation, run the engine at varied throttle settings up to 4500 RPM or at three-quarter throttle, and during this period of time run it at full throttle for approximately one minute every ten minutes. (The only one advocating full throttle during first 2 hours.)

3. For the next eight hours of operation, avoid continuous operation at wide open throttle for more than 5 minutes at a time.

Yamaha break-in is very similar to Suzuki.

Finding the best cruising RPM/Speed, also requires proper trimming of the boat. Many do not experiment to see what trim gives the best fuel economy and ride at cruising RPM. There are times when the bow needs to be trimmed down when going into chop, or up when going down wind/waves, to give best/safe ride, and compromise on the best fuel efficiency.

I find that there is not just one speed--it depends on conditions.
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robhwa



Joined: 04 Dec 2013
Posts: 298
City/Region: Anderson Island
State or Province: WA
C-Dory Year: 2003
C-Dory Model: 22 Cruiser
Vessel Name: Marcia C
Photos: Problemadela
PostPosted: Wed May 04, 2022 1:17 am    Post subject: Reply with quote

Peter & Judy wrote:
Quote:
The goal is to find your engine's "sweet spot" for the long cruises. That sweet spot
can be somewhat customized to your usual boat load by selecting the best engine
power/propeller combo from the start.


There are two sweet spots for my boat and my boating style. I find that I cruise mostly at 2400 RPM (6 Knots) and 4400 RPM (12-14 knots). My typical cruise is 10 - 14 days long, so heavily loaded. This speed combo gives me the fuel efficiency that I want and the speeds that I enjoy. I boat primarily off Vancouver Island and I want to keep my speeds to a comfortable and safe level. In these waters there is a lot of logging activity and you need to keep a sharp eye out for floating logs and deadheads. I have had a few close calls, especially when the water is choppy and the logs are hiding amongst the waves. WOT is just too fast for my liking and safety.

Excellent guidelines from someone that knows local conditions. Operating consistently at WOT is a good way to support repair shops, and boaters around here quickly learn their limits the hard way. I was fishing at Neah Bay (the most western point in the continental USA), last week. Good fishing. We would never consider operating at WOT unless glassy, which is rare. Usually the boats that you see really "go for it" are new, with new, overpowered motors on the stern. Even at slow plane, we managed to hit a submerged, invisible, log, on this trip, which bent the prop and broke off part of the antiventillation (caviation?) plate. I have never met anyone here that boats a lot that has not had some experience hitting things, and the faster the speed, the worse the damage. Outboard motors seem particularly vulnerable since they do not generally have prop protection from keels.
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