Honda 9.9 or 15hp for CD25?

[Nick Armstrong]

I'm looking into a new OB for my CD25 #288 '75. Previously a Johnson 9.9. Will the Honda 9.9 or 15 fit and which one is perfered? At times I thought the 9.9 was a little light for some strong currents but it was OK for the most part. Any thoughts?



nicka1@compuserve.com

[Tom Foley]

I'm looking into a new OB for my CD25 #288 '75. Previously a Johnson 9.9. Will the Honda 9.9 or 15 fit and which one is perfered? At times I thought the 9.9 was a little light for some strong currents but it was OK for the most part. Any thoughts?

I have asked a similar question about my recently aquired CD25. I learned that some use a 6 or 8 HP motor with no problem. Its also ver y important to have a low pitch prop. A nine inch prop with a 5 pitch was suggested.

Tom Foley, Kennebunk, Maine



alewifehouse@mainecoast.net

[jim stull]

I'm looking into a new OB for my CD25 #288 '75. Previously a Johnson 9.9. Will the Honda 9.9 or 15 fit and which one is perfered? At times I thought the 9.9 was a little light for some strong currents but it was OK for the most part. Any thoughts?

I installed a Honda 8 HP in my CD25 last season.
It seems to have more than enough power. In fact it will push the boat to hull speed with the throttle setting just barely off the start position.
If you decide on the 9.9 check the clearances carefully as the 8 HP is already a VERY snug fit. I had to fabricate a new mounting board to move the engine forward sufficiently to clear the rear of the well.
Also the existing motor well drop boards and track had to be discarded due to interference with the shift and throttle controls. I made new ones that mounted outside the well opening. You will also most likly have to modify the plug for the alternator output.
The motor well cover required raising about 1/2 inch with my setup.
Additionally if the 9.9 is wider than the 8HP the engine width should be checked for interference with the gas tanks.
I am very happy with the Honda 8 HP except for the well known exaust fume problem. I made provisions to feed fresh air to the engine but it has been only partially succesfull. I plan tapping the exaust port and piping out the fumes as one of this winters projects.
A search of this web site will turn up Dana's solution to the problem, (he uses a Yamaha in a CD26), which I plan to adapt to the Honda.
Good Luck
Jim



jtstull@icubed.com

[Larry Niles]

I'm looking into a new OB for my CD25 #288 '75. Previously a Johnson 9.9. Will the Honda 9.9 or 15 fit and which one is perfered? At times I thought the 9.9 was a little light for some strong currents but it was OK for the most part. Any thoughts?

I have a honda 9.9 on my cd26 #12 '85. I have no problem reaching hull speed in any condition. I was told the four stroke engines develop more thrust than comparable two strokes, so it may account for your problem with the johnson. The fit is tight and I also had to alter the mounting board to develop rear clearance. I also have an exhaust problem which I hope to correct in the same way as Jim Stull.



nilesl@algorithms.com

[Ed Roberts]

Regarding the choice between a 9.9 and a 15, the specs for these two engines are absolutely identical except that the 15 can develop some additional HP at very high RPMs. But you can never utilize this because of the very low hull speed of a sailboat (as opposed to a small planing powerboat.) I understand the reason for this is to beat a widespread regulation on many lakes that forbids motors over 10 HP, so manufacturers simple detune their 15 HP motor. The Honda catalog I have describes the 15 as "well suited...for sailboats" but describes the 9.9 as "ideal...for sailboats."

Will the Honda 9.9 or 15 fit and which one is perfered?

edwardroberts@sprintmail.com

[john churchill]

I'm looking into a new OB for my CD25 #288 '75. Previously a Johnson 9.9. Will the Honda 9.9 or 15 fit and which one is perfered? At times I thought the 9.9 was a little light for some strong currents but it was OK for the most part. Any thoughts?

ive got a 15 honda in my cd26. i thought it was way overkill until i got into a 35 knot headwind and 5 foot (honest) seas running against an outgoing tide. i wanted a bit more. the difference between a 9.9 and a 15 is in the carb jets and also in the governor. the 28" shaft model has a 10 amp alternator which is nice. in the above story, my 28" was coming out of the water at the crests. i think an inboard would have done the same.

[Bob Flayhart]

Jim,
How did you raise the lazarette cover? I am assuming by using spacers. Also in ref. to the emissions, I am currently using a 2 stroke. Is the exhaust as bad. How far did you have to move the motor mount and how was it accomplished? I am not a fixer upper so I need assuance that it can be accomplished with a minimal of skills.

Thanks & regards,
Bob



ctr6259@vicon.net

[Jim Stull]

Jim,
How did you raise the lazarette cover? I am assuming by using spacers. Also in ref. to the emissions, I am currently using a 2 stroke. Is the exhaust as bad. How far did you have to move the motor mount and how was it accomplished? I am not a fixer upper so I need assuance that it can be accomplished with a minimal of skills.

Thanks & regards,
Bob

You are correct Bob, I used spacers under the hinges to raise the lid. The amount was minimal, maybe within the origional fiberglass fabrication tolerances. Check to see if your boat may have the additional space. (Probable less than an inch.)
The emissions are still unacceptable. Most days I had to prop up the lid about 2 inches to get the engine to run correctly. I plan on implementing a version of Dana's solution before returning the boat to the water.
No one problem in the mod was that difficult. Pull out the existing mounting board and bracket and the drop board tracks. (I had removed the traveller system to install a heavy duty Harken system, if you leave this in place you will probably need to temporally remove the motor control arm. Not a big deal.) If you can rig the engine so that you can lowerer it into the well and suspend it while you think about what you need to do, the problem will explain itself to a large degree. I fooled around trying to "hold" the engine in place and at the same time work out the problem. I am a slow learner but eventually I figured out that I would never get it done that way. (Having my 5'2" wife try to hold it was even very much worse").
The fit is very very tight and I imagine each boat will be a half an inch different here and there so my dimensions would most likly get you into trouble.
I found it very helpfull to "mock-up" a trial piece with scrap wood to get the final fit correct (mainly the motor mounting board).
One of the boat building authors wrote that his thinking chair, in the boat barn, was his most valuable tool. I find this to be true. Once the new engine is suspended in the well, sit down and think about what must go where to hold the engine in place etc. You may be supprised at how good a fixer-upper you realy are, once you can visualize the problem.
If you decide to go ahead and have specific questions give a shout.
Jim



jtstull@icubed.com