repowering my sailboat- engine selection

[Dave9111]

I don't think anyone is "bashing him". He can do what he wants. However he might glean some wisdom from what makes sense to other users who have "been there, done that", and still have the hole in our wallets.
If I was a diesel mechanic in a boat yard, I'd be looking for boats in otherwise good condition that had a stuck engine, broken tranny, etc. Repair the engine, tranny, etc and flip the boat. Find another one and repeat. Do that a couple of times and he might find himself sitting on a 50K boat. The boatyards I frequent are FULL of $1000 boats.. rotting in their stands. Sad but true.

[Cheechako]

The Cat 27 came with an inboard diesel, so it's readily do able. Not sure it's worth it on a small inexpensive boat like that. But that's your choice. Anything from maybe 6 HP up to 15 or so should be fine. My heavy Contessa 26 had a 6 hp Bukh diesel in it.
But I would suggest you use your boat for a while this year and then decide. You could make a lifting device that slides the outboard up vertically in the well.

[Rotten Ricky]

Having towed other boats away from rocks, had to bash against standing waves to get out of danger, and watched other outboards screaming in the air on hobby-horsing sailboats in the cold BC waters, I am glad I re-powered the two outboard engines on my tri with a single Kubota-based diesel slightly larger than the design specs.

The time to assess engine size is not when you are in safe, flat water, but in an emergency! It has nothing much to do with hull speed and everything to do with SOG when you are being held back by conditions or circumstances. Even many naval architects seem to forget this important fact.

The north-west coast can be a hazardous place with help and fuel stations far apart - and that fuel tends to be diesel for commercial boats, not gas for pleasure boats.

As a bonus, I get reliability, lack of easy theft, heating in the cabin, and great battery charging capacity. And peace of mind! The drag of the prop (soon to be eliminated by a feathering prop) is offset by having a better balanced boat without an unsightly weight hung out of the stern. The bigger engine will be slightly heavier and more expensive, but it will last longer - just remember to run it flat out on occasion to blow the soot out.

Good seamanship includes having a well-found vessel that is ready for anything. Nothing should Trump safety. (Oops!) Go for a 20 HP diesel such as the Beta.

Happy sailing and cheers, RR.

[crashkahuna]

For what it's worth my old Pearson 27 with slightly higher displacement had 12hp universal 2 cyl diesel. It seemed ideal size for boat.

[hriehl1]

For what it is worth, consider your usage as there is no right answer.

I have a similar boat, a vintage Hinterhoeller HR28 with a purpose built outboard well and stern cutout for raising the outboard. Importantly, I am a fair weather daysailor with need to motor maybe 200 yards to/from the mooring. So my power needs are modest.

I just bought a 9.9 Suzuki hi-thrust which moves me thru 3 foot seas at over 5 knots. Sadly, the powerhead is so big the engine cannot tilt full up. I wish I had bought 6 or 8 hp model that fully tilts as getting that leg out of the water really reduces drag and improves speed.

The point of that is to advise that your power needs depend on your use cases, how long do you motor and in what weather conditions? It is a sailboat after all, what really are your motoring needs?