Hello, I have a Catalina 27 I've had on the lake for 4 years. I am about to move it into the bay (Corpus Christi area) and am asking for anyones thoughts on a sufficient outboard for it. I currently have a 2013 Tohatsu 9.8hp on it. While its been very dependable and got the job done I've always found it a bit lacking in power, especially in cases where I have a few extra people and coolers aboard. I am thinking coastal waters and winds are not going to improve this. Everywhere that I have read people say 10hp should be fine for a 27 ftr though. It's possible it needs tuning. I have been looking into replacing it. I have a 20" shaft currently and thought going to the 25" may not be a bad idea for choppier water. From what I've found this is only available on the 9.8 or 20hp, as I was considering the 15hp. The shaft can possibly be changed out? I don't believe the weight difference is very significant between the 9.8 and 20. Is a 20hp with a 25" shaft a good choice for the 27 in ocean water and what are your thoughts? Thanks for any input.
Catalina 27 outboard hp question
- Thread starter Catalina27
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I had a Catalina 25 with a 9.8 and it was overpowered. I changed it to an 8 and that was fine. 9.8 should be fine for the 27 but get the long shaft. You don’t want too much weight in the stern as it will increase pitching of the boat. The boat can only go hull speed so excess power just adds weight with no benefit.
I have a 9.9 on an O'Day 25 and find it under powered. The extra thrust is very helpful for control as well as emergency stops. However, getting that prop lower will make a very noticeable difference. Everyone debates on how much power is necessary but never about getting the prop as low as possible.
As Kloudie suggests, switch to a high thrust prop. For a vessel whose max speed less than kts, the change in pitch will allow the motor to operate more efficiently. I have one on my OB and the performance change was dramatic. Also, be aware of the added weight hanging off the back in choppy seas. But the very big consideration is the 25" shaft, which will definitely interfere with the Cat 27's notorious swept back rudder. Even the 20 inch shaft is difficult to mount perfectly vertical with that rudder.
I had a Chrysler 9.9hp Sailor 250 on an ODay 25. It was a fine motor for that boat, electric start, alternator, and geared down for a bigger diameter, reduced pitch prop (the 250 was for 250lbs thrust).
Any outboard that is geared down to swing a bigger prop will perform better on a sailboat. And getting the prop deeper certainly helps.
Fred W
Any outboard that is geared down to swing a bigger prop will perform better on a sailboat. And getting the prop deeper certainly helps.
Fred W