Outboard on a Catalina 27

[new-to-sailing]

Hello everyone, I am planning to add an outboard to my Catalina 27, it will likely be a short term situation (1-2 years) so thinking about how I could reuse the outboard I buy for a dinghy down the line. A few questions related to my plan below.

1. I am planning to buy a 5hp Tohatsu Propane, I believe this should give me the power I need. I will only need this for getting in and out of my slip and the occasional longer trip which would only be in calm conditions. I have seen some who say this is fine, others suggest going for more HP, anyone have thoughts on this? Or better yet is there any sort of calculation that can be done given hull etc. to see how this will fare.

2. Most people use a 20” or longer shaft it appears for this type of application, if I install a bracket that allows the prop on a 15” to be installed as intended is there any other reason I should use a long shaft? A big reason I want to use the 15” shaft is to make this outboard more usable for a dinghy down the line.

3. Any recommendations for outboard dealers in the Chicago area? Or recommendations for adjustable outboard brackets?

I know there is a lot on here and certainly a well discussed topic but any thoughts or other resources on this would be great! Happy to clarify if needed.

[thomm225]

A 5 hp outboard will work on a Catalina 27 but get the 25 inch shaft so it doesn’t continually pop out of the water.

I use that size on my Bristol 27.

Also order one online. It’s usually free delivery. They weigh around 58 lbs.

Get an adjustable bracket like Panther.

[Adelie]

Don’t get the propane. Nice idea in some ways but not if you are going to use it later on a dinghy.

Get a 6hp, extra-long shaft hi-thrust (Tohatsu calls them Pro-sail).

The extra long so it doesn’t come out of the water in bouncy conditions.
That Tohatsu also comes with a small alternator for recharging batteries.
High thrust gets you more thrust at lower speeds (displacement speeds for the mothership and hole shot for the dinghy).
For the mothership this translates into significantly better fuel economy at the same speed or a slightly higher top speed at full throttle.
For the dinghy the extra power for the hole shot is likely to be the difference between getting on a plane or not. Total weight and load distribution will also have an effect on whether you get in a plane. 5hp is very marginal for planing a dinghy, 6hp is better without adding weight and high thrust better still. The highs thrust will cost you 2-3kt off of top speed but if it’s the difference between planing or not or having to spend more money on a bigger engine it’s worth it.

Get gas rather than propane unless you will never use the dinghy over long distances or for extended periods away from major metropolitan areas. Propane occupies a significantly higher volume for equivalent amounts of fuel and its heavier due to the pressure containers required to store.

[pdx_sailing]

I had a 9.9 electric start yamaha long shaft with remote controls mounted in the cockpit of C27 15 years ago. It would charge the batteries and pushed the boat around with out issue in the columbia river current. 5Hp seems low for that boat.

[Adelie]

Survey of what HP would get how many people on a plane with various types of dinghy:

https://www.cruisersforum.com/forums...ml#post3516272

[thomm225]

Originally Posted by Adelie

Don’t get the propane. Nice idea in some ways but not if you are going to use it later on a dinghy.

Get a 6hp, extra-long shaft hi-thrust (Tohatsu calls them Pro-sail).

The extra long so it doesn’t come out of the water in bouncy conditions.
That Tohatsu also comes with a small alternator for recharging batteries.
High thrust gets you more thrust at lower speeds (displacement speeds for the mothership and hole shot for the dinghy).
For the mothership this translates into significantly better fuel economy at the same speed or a slightly higher top speed at full throttle.
For the dinghy the extra power for the hole shot is likely to be the difference between getting on a plane or not. Total weight and load distribution will also have an effect on whether you get in a plane. 5hp is very marginal for planing a dinghy, 6hp is better without adding weight and high thrust better still. The highs thrust will cost you 2-3kt off of top speed but if it’s the difference between planing or not or having to spend more money on a bigger engine it’s worth it.

Get gas rather than propane unless you will never use the dinghy over long distances or for extended periods away from major metropolitan areas. Propane occupies a significantly higher volume for equivalent amounts of fuel and its heavier due to the pressure containers required to store.

You can forget about planing with a 25 inch extra long shaft outboard.

It will be too deep in the water.”

[OldManMirage]

So you're between a rock and hard place.

For a dinghy you only want a short shaft. For a sailboat like the C27 you'd really prefer as long as possible.

But I would say for what you want to do, get the short shaft. And 5hp will be fine for getting in and out of the slip and for motoring in calm waters. If the wind is against you it will slow you down though, so be aware.

I would skip the propane though. It's just not worth it. Get a gas.

[thomm225]

If you get a gas outboard, you might want to get a Mercury 5 HP because they have the integrated or onboard fuel tank.

So if you are just using the engine to come and go from your slip, you don't have to hook up the external tank.

Same with controls. They just clutter up the cockpit.

I was planning on just using my outboard to come and go from my slip also but have used it quite a bit to motor home from 20 miles away or more on many Sunday mornings to get back so I'd be ready for work on Monday

And many times when I did this I needed the full 25" extra long shaft outboard because sometimes it would be a bit rough

Also, Online Outboards has free shipping.

https://onlineoutboards.com/?gclid=E...SAAEgJUJfD_BwE

https://www.youtube.com/watch?v=cpZhq35etcw

[Mickeyrouse]

Motor demands for boat propulsion are not identical to those for dinghy use. Depending on where you carry the dinghy and its motor, those 58 lbs will be heavier than you think. Many dinghy kickers ride on a stern rail mount when not in use, and are lifted off the rail and mounted onto the dinghy transom in the make-ready process. If that’s your drill, depending on that stern rail height above water, you will be standing up in your dinghy lifting those 58 lbs about to eye level to return it to its mount when the dinghy ride is over. If there is any kind of chop, you are now standing straight up with both hands fully occupied in the most unstable posture you can be in on a dinghy.
Our kicker is a 5 HP Merc two-stroke that weighs 38 lbs with no fuel . Mounting and de-mounting has always been an unpleasant task. I forever have the feeling of pitching head over heels with the kicker in my hands while I am doing this. It takes two people to safely do this. 20 more lbs would make the process impossible.
If you plan carry the dinghy on davits with the kicker permanently mounted, you won’t encounter this. But dinghy davits on a 27ft boat?
Propane sounds nice for fuel on a boat propulsion motor. But the idea of a propane bottle bouncing around the dinghy floor with life jackets, feet, groceries, maybe a dog, other dinghy gear….I’d have to get used to that one.

[Don C L]

I'm with OldManMirage on this one. You can get by with a 5hp short shaft to get you in and out of a slip and to motor about 3 to 4 kts in VERY calm water. I would also avoid the propane and look to Catalina Direct for a long throw motor mount:
https://www.catalinadirect.com/shop-...earchResults=1

[new-to-sailing]

Originally Posted by Adelie

Survey of what HP would get how many people on a plane with various types of dinghy:

https://www.cruisersforum.com/forums...ml#post3516272

Interesting thread, didn't see any commentary on the Shaft Length assuming most had 15". I supposed I could experiment with raising the transom etc later down the line or modifying the shaft length?

[new-to-sailing]

Appreciate the replies! Great to see an example of someone powering a similar sized boat.

I am going to go with the long shaft (20") as in the short term powering the sailboat is more of a priority. I shouldn't have any issues mounting it fairly close to the water getting a lot of the shaft submerged so don't see a ton of upside for the 25" especially if I consider future dinghy use. I will also get one of the sailpro models.

I am still torn between the Propane and gas, if I am not worried about availability of the propane are there any other downsides? I like the idea of using propane for storage, fuel quality, and simplicity. I've also read that the carburetor on a gas engine can have issues if not run frequently (I have no experience with gas engines) so keeping the system simple and lower maintenance certainly a plus for me.

[NorthCoastJoe]

I had in the past a Leer 5 hp propane that held a #1 camp stove bottle of propane on the engine. So no need for a big bottle.

If you go with gas when you shut down disconnect / shut off the fuel and run it until it uses all the fuel in the carb and you will have no problems. Do that with all small motors.

I have been doing that with a chainsaw that is now 35 years old and I have never had a problem, never touched the carb in 35 years.

You might get a good motor on Craigslist. I have gotten a few that way.

[Adelie]

Originally Posted by Don C L

I'm with OldManMirage on this one. You can get by with a 5hp short shaft to get you in and out of a slip and to motor about 3 to 4 kts in VERY calm water. I would also avoid the propane and look to Catalina Direct for a long throw motor mount:
https://www.catalinadirect.com/shop-...earchResults=1

When I learned to sail keelboats we had a 6hp 2-stroke that could push an Excalibur 26 to hull speed.

AtomVoyages has been installing hi-thrust outboards on various larger boats.
6hp got an Alberg 30 to 5.5kt in reasonably flat water.
6hp got a Pearson 365 to 4.2kt.

A 5hp should have no problem getting a Cat-27 up to or nearly to hull speed in flat water.

[sanibel sailor]

Get what works for the C27. Temporary arrangements tend to become permanent when the other solution is expensive.