Moving to a smaller outboard?

[Kingmann]

I have a 22’ cruiser with 90 HP. It is carbuerted (4). I am thinking of a new motor with electronic ignition. I would like to get a lighter engine but how low can I go before getting into trouble with plan and cruising at low rpms? One of my goals is to have the boat plane at lower speeds. :?:

 

[ssobol]

The planing speed is determined mostly by the hull shape and the boat gross weight. A lighter engine will reduce the boat weight and therefore the planing speed and the power required to get to that speed. But the change in overall weight of the boat by going from a 90 hp to a smaller engine is not that much. The Honda 75 weighs the same as the 90. Going to the Honda 60 will save you about 100 pounds. That's about 2% of the weight of a typically loaded 22 cruiser. You probably won't notice the change in planing speed.

 

[hardee]

Unless you are planning on doing all your cruising at hull speeds I would not plan on going to a 60hp outboard. You might be able to plane a 22 with a 60, but that would be for a very light boat. (2 small people on board, maybe a sack lunch and a fly casting reel.) I run twin 40's for 80 HP. I would not want anything less than that for power.

I know there are some 22's out there that are running 70 hp, but not many. In 14 years I have seen a couple. If I were repowering it would be to 50's (x2).

A typical planning speed for a 22 Cruiser is 9-10 knots. Maybe 8 with trim tabs or a Permatrim. Those are both options you might consider. OR, you may need to go to a different, lighter engine with the same power rating.

Harvey
SleepyC :moon

 

[DavidM]

Consider the Yamaha 4 cycle 70 hp outboard. It is just 1 liter so it is light- 258 lbs.

I can't speak to whether it will plane a CD 22, but I strongly suspect it would do just fine. It planes my Pompano 23 nicely at 15 mph at 4,600 rpm while propped to reach 6,000 at wot.

David

 

[Sea Wolf]

Here's my two cents:

The lighter engine approach is valid, but of diminishing returns.

Also, as you accumulate time with the boat, "stuff" you add for safety, functionality, convenience, and whatever .... eventually loads up the weight factor against you. Especially if you'e into cruising or fishing.

Here's what I'd do for an engine choice instead. Might seem counter-intuitive at first, but think about it!

https://boattest.com/engine-review/Evin ... -H-O-_2014

Good Luck!

Joe. :teeth :thup

 

[DavidM]

I too like the Evinrude ETEC's, but the under 150 hp versions are still the old Gen 1 engines. The newly designed Gen 2 engines (150 hp plus) beat the 4 cycle competitors in most catagories, particularly torque for quick planing and fuel consumption.

The older designed 90 hp ETECs don't do as well. They probably do ok in torque and acceleration but are far short of their competitors in fuel consumption.

Let's hope that Evinrude comes out with lower hp Gen 2 versions soon.

David

 

[pcg]

The older designed 90 hp ETECs don't do as well. They probably do ok in torque and acceleration but are far short of their competitors in fuel consumption.

Are you saying that the E-TEC 90 is "far short of [EFI Honda 90] in fuel consumption"?

Let's hope that Evinrude comes out with lower hp Gen 2 versions soon.

At Seattle boat show, Evinrude rep told me that there are no plans to bring Gen 2 to anything less than 150 hp (available this spring) and that Gen 2 motors are substantially heavier then Gen 1.

My impression, after talking to multiple dealers and reading multiple forums, is that the E-TEC 90 is as good or better then the Honda 90 in fuel consumption, has slightly better low end torque, is 70 lbs. lighter, is easier and less costly to maintain, but is more expensive and a bit noisier than the Honda.

 

[Foggy]

I agree with Joe. Boats, like most people, gain weight with time.
That means a smaller engine will be less effective in its ability to plane the boat.
Moreover, the smaller engine will have to 'work' harder, have less economy and
maybe shorter life than one with more HP.

I've enjoyed and not regretted having larger engines working less, staying cool
and thumping along with the ability to scoot when desired. May not be possible
with too much downsizing.

Aye.

 

[NewMoon]

We repowered our CD22 from 70hp to 90hp (both 2-cycle Yamaha), after our first cruise in the San Juans and Gulf Islands. With all the stuff we carried for extended cruising and fishing, and a full 58 gal fuel tank, the 70 struggled to plane. The 90 was much better - ran without straining through a two month SE AK cruise with even more stuff.

If you will be carrying a lot of stuff, I would think 90 would be the smallest you would want.

 

[DavidM]

Are you saying that the E-TEC 90 is "far short of [EFI Honda 90] in fuel consumption"?

Yes. Even though outboard manufacturer's never give fuel consumption data unlike diesels, Boattest.com does test boats with these engines. Their test data shows that the Evinrude Etec 90 uses 11.0 gph at wot to make 90 hp whereas the Honda uses 9.6 gph to make 90 hp. Wot fuel consumption doesn't tell the whole story throughout the power band and Gen 2 Etecs do much better at mid rpms but they also roughly equal an equivalent Honda at wot.

So my conclusion is that the Evinrude Gen 1 Etec 90 uses about 15% more fuel than the Honda.

BTW here is the Boattest test of the CD 22 with the Honda 90: https://www.boattest.com/review/c-dory/1455_22-cruiser

Looking at that data tells me that 70 hp would definitely give you a cruise in the mid teens mph but if you want to cruise in the low 20s then go with 90 hp.

David

 

[pcg]

Boattest.com does test boats with these engines. Their test data shows that the Evinrude Etec 90 uses 11.0 gph at wot to make 90 hp whereas the Honda uses 9.6 gph to make 90 hp.
David

Different motor...
I believe that was a test of the ETEC 90 H.O., which is a four cylinder motor designed for high performance and is as heavy as the Honda 90.

The standard ETC 90, which is lauded for its fuel economy, is a three cylinder motor and is 70 lbs. lighter. I don't think Boattest has tested that motor.

 

[ssobol]

Some people on other forums point out that while the fuel cost for the 2-cycle might be less, the $30/gal oil that is required can negate a lot of those savings. I guess you get some additional savings by not having to do oil changes, but how much does that really save (I do them myself)?

FWIW, Boattest seems to do their tests using boats that weigh a lot less than a typical CD-22 cruiser.

 

[pcg]

I guess you get some additional savings by not having to do oil changes, but how much does that really save (I do them myself)?

Well I'm out on a limb here because I own neither an ETEC nor a Honda motor. I'm just reporting what I've learned and I hope people will correct me if I'm wrong, preferably before I buy a new outboard.

My understanding is that other savings come from a simple once every three year maintenance for the ETEC vs. a more complex (more $) annual maintenance for the Honda. Also the ETECs basically automatically winterize themselves with a simple throttle maneuver.

 

[ssobol]

...
My understanding is that other savings come from a simple once every three year maintenance for the ETEC vs. a more complex (more $) annual maintenance for the Honda. Also the ETECs basically automatically winterize themselves with a simple throttle maneuver.

Other than changing the engine oil, I can't think of anything needed on a 4-cycle that is not needed on a 2-cycle. AFAIK, you still need to change the fuel filters, the lower unit oil, the water pump impeller, and occasionally the spark plugs. It only takes a couple of hours (if you work slowly).

My Honda automatically winterizes itself. Just tilt it to the vertical and let the water run out. Done. I guess it might depend on what kind of winter you have.

The Etec 300 service interval may also only apply to motors used in fresh water.

 

[Chester]

My 22 planes at ~10 knots which is typical I think. It does have Doel fins on the AV plates.
Asking to plane at an even lower speed is not realistic IMO.
Underpowering a boat is an expensive, disappointing mistake. The engine will struggle and have to turn high RPMs at whatever speed you can make.
Will the 70 hp Yamaha work? It is a highly tuned engine that makes a lot of power for it's displacement. This means the power comes in at high RPM and it likely has a weak low and mid range. I suspect it would be an unhappy marriage with your 22.

 

[thataway]

I like Yamaha outboards, and would buy a 200 If repowering my 25... But the 70 1 liter is basically the 50 tuned up--as noted by several, the power will be at the high end, not the low end where you want to be to get on a plane. You could decrease the prop pitch, and run the motor at high RPM...Interesting where Yamaha talks about their "Powerful" 17 amp alternator (Same as OP's Honda, and Evinrude brags about their 133 amp magneto--with 50 amps for battery charging--and 83 amps to run the engine..Yet the Fuse is only 10 amps...I haven't figured that one out yet!

I have talked to several who have owned 22's with a 50 hp--they can get on a plane at 12 to 15 MPH. Almost all who have bought a 22, with a 50, used, have repowered.

A lighter boat will plane at a lower speed. Trim tabs and foils (which I believe all C Dorys should have, certainly help get on a plane at lower speeds.) But my 22's were closer to 10 to 12 knots to get on a plane.. (I run a heavy boat--often with cruise gear, food, etc for a month.)'

If I were repowering, I would go with a larger engine-- 115 hp.

 

[ssobol]

Maybe split the difference and get a Honda BF100. BTW, the Honda BF75. BF90, anf BF100 are all the same engine. Except it seems that the 100 needs premium gas to get 100hp out of it.