Repower CD28-Beta 14 or Beta 16

Discussions about Cape Dory, Intrepid and Robinhood sailboats and how we use them. Got questions? Have answers? Provide them here.

Moderator: Jim Walsh

Post Reply
RichardM
Posts: 12
Joined: Dec 14th, '05, 13:45
Location: Trilogy

Repower CD28-Beta 14 or Beta 16

Post by RichardM »

Our Volvo MD7A will be removed and will be available for parts in July. We are in the process of selecting a Beta Marine engine either the 14 or 16 model. Talking with the rep at Beta he tells me that CD 28 owners have installed both and liked them. I am concerned with having adequate power into head winds and current. Which is a better choice or is it more a question of prop size? Any recommendation on the Beta 14 or 16?
User avatar
Joe CD MS 300
Posts: 995
Joined: Jul 5th, '05, 16:18
Location: Cape Dory Motor Sailor 300 / "Quest" / Linekin Bay - Boothbay Harbor

Re: Repower CD28-Beta 14 or Beta 16

Post by Joe CD MS 300 »

New engines are in general a fair amount lighter than older engines of comparable HP. I’d go with the size closest in weight to the original unless there are re-prop considerations so as not to change the waterline trim much. I repowered a 46 hp Westerbeke with a 55 Westerbeke which if I’m remembering correctly was about 75 lbs lighter. The trim might be more of an issue if you have an all chain anchor rode.
Better to find humility before humility finds you.
sgbernd
Posts: 265
Joined: Mar 3rd, '06, 11:53
Location: Valhalla
CD-28 #359
Ventura, CA

Re: Repower CD28-Beta 14 or Beta 16

Post by sgbernd »

I chose the 16 when I re-powered in 2016 but I imagine the 14 is fine as well. Ben Thomas, the dealer, put the 13hp (same engine previously) in his CD-30 and it is fine. Unfortunately I can't compare them as I've only experience with the 16.

My logic was that I needed about 12.5hp to move at hull speed (5.5kts) in still water. The chart showed the 16hp developing that power at 2500-2700 rpm and the 14hp developing that power at 3,250rpm. Thus, either is suitable, it is just a matter of preference and tolerating a bit more noise and vibration due to the higher operating speed of the 14hp. For me, the price, size and weight differences were not of concern and there is no difference in life expectancy as both are rated for far more hours than leisure sailors will ever see.

In retrospect, with 400hrs on the clock, I've used full power a only a couple of times (entering the harbor between sets when the swell was dangerously high) and feel the 16 is slightly over-powered on the CD28 which suits me fine. She cruises at 2500-2700 rpm at 5.2kts in still water and at full power (3,600rpm) will hit 6.8-7kts in still water. But at 7kts, she is digging in pretty deep and leaving a good sized wake.

Additional consideration: The 14hp is based on the Kubota 482 which is used for shipping containers, reefers, etc. If you look on ebay, there are always dozens of scrapped ones available. The 16hp is based on the Kubota 602 which is rather rare. If, for some reason, you ever needed a replacement block, head, injector pump, etc, it is much easier and cheaper to find a scrap 482 than a 602. That said, unless you plan to run it out of oil or coolant and severely overheat it, I can't imagine ever wanting a used spare block or head.

In conclusion, either choice is fine and merely a matter of preference.

Steve Bernd
User avatar
Ben Thomas
Posts: 215
Joined: Feb 5th, '05, 12:17
Location: 82 CD30 Milagro Hull #248

Re: Repower CD28-Beta 14 or Beta 16

Post by Ben Thomas »

Actually I repowered with the Beta 20. I re-fit a Balmar 100 amp. alt on it with a 3K serpentine belt and pulleys which when in full swing drops the HP to around 16. (house bank is 630 amps)
I have rarely had the engine at full RPM, (3600) only a few times while crossing the Columbia Bar have I had her up to 3500 RPMs.
Physics will only let the displacement hull travel at its hull speed and very little beyond while under power, the stern will begin to squat and the stern wake will catch up to you and there you are.
The big advantage to the few extra HP is bucking strong tidal currents, headwinds and such when motoring or motor sailing.
The 16 with the standard 40 amp. alt. will do much the same thing on the 28, you will reach hull speed easily at around 80% of rated RPMs which is at the peak of the torque curve when having the correct gear ration and prop size
Cheers
Dave and Kathy
Posts: 31
Joined: Sep 7th, '10, 17:45
Location: CD28 and Typhoon Weekender

Re: Repower CD28-Beta 14 or Beta 16

Post by Dave and Kathy »

Our 1984 CD 28 came to us with the original Universal M-18 and we re-powered with the Beta 16. My logic was that, since the M-18 was de-rated to an actual 14hp, the Beta 14 could have done the job. However, we are on the Columbia River and have currents and locks to deal with. The Beta 16 is about 70 pounds lighter and delivers the extra 2hp. The difference in price between the Beta 14 and Beta 16 was worth paying. We ordered the optional high-output alternator as well. Love the engine!
Dave and Kathy
Post Reply