TOPIC: outboard selection

Getting ready to restore my 1960 Dorsett Catalina. It needs everything accept the ability to float. This may be a faux pas, but I want to put a modern outboard on it. The transom is 16 inches, so I am having trouble finding mid-range horse power with any thing less than 20 inch shafts. The only NIssan with a 15 inch shaft I can find is a 20 hp. I was thinking 90 hp which may by overkill for this boat. Any suggestions or advice. I am new to boating and know very little. I appreciate you time.

Short shaft in that HP has been obsolete for years.

You're probably gonna have to install an adjustable-height stern bracket (jack plate) and run a long shaft motor. Here's a fellow at this site with similar boat, running a 40hp long shaft Tohatsu and I imagine the transom on that boat was built to long shaft specs during the restoration:

www.fiberglassics.com/gallery/category/218-1960-dorsett-catalina-modified-restoration.html

You might get hold of him and ask how well the 40hp pushes a 17' boat.

Do you have a "Max Allowable Horsepower" rating on your boat mfr's Model/Ser # info plate? Maybe not, since it's so old. I wouldn't consider a 90hp too much motor if the transom is in good shape. A 75hp 3-cyl Merc would push it nicely as well, but you're looking at a long shaft motor there, too. They made that Triple in a 90hp flavor as well.

If you thought a 50hp might push it OK, a Merc 44-Cube 50hp (in many flavors from the early '60's thru somewhere in the late 80's), had a transom height of around 17" (as I recall) for the short shaft motor. They definitely are longer than 15", even though the long shaft motor is a 20" transom height. Easy enough to space the engine up a bit in that case. Short shafts on the later motors are few & far-between, but it is possible to convert. Requires some wrenching and parts searching to do that, though.

Anyway, the big thing is to determine what hp level you need to push your boat the way you'd expect; One you've got that down, the mounting requirements follow.

I bought a stern bracket/jack plate for my 12' runabout last year from Bob's Machine Shop. They have an in-house engineer-type to consult with and were very helpful with my needs. Not cheap but you do get what you pay for.

www.bobsmachine.com/

They have jack plates with power-operated lifts to adjust transom height, there are manually-adjustable ones as well. You can get a plate that tilts & trims, if the engine you get doesn't have PT&T built-in.

HTH & keep us posted. Whatever you end up with, we should be able to figure out how to hang it on the back of your boat!

And,...If you ever change your mind, and consider a vintage motor,
The Mercury 80 HP 4 cyl of the late '70s through the late '80s would be a good one for the Catalina.
So would an OMC 3 cyl, the 70HP?, 75HP, and ??? would probably make a good motor for the Catalina.
I have attached some pictures of a sweet rebuilt 85HP 4 cyl Merc with PT that I did, and installed for a pal.
IMHO,...The 85HP 4 cyl Mercs are the perfect horse power for the Catalina.
I'm not sure, but I believe that when Mercury started installing low dome pistons, and also started rating the HP at the prop rather than the flywheel,...The 85 became a 75HP.
doc F

I'd go with what doc said. He did a 80 for my friend with a Dorsett El Dorado and looks perfect! Pix...

If your Catalina needs "everything" as you say, then a new transom at 20" would solve "everything".
The transom in my 1961 Catalina was totally shot, but was made of only 1" plywood originally. The Catalinas of the early 1960's were rated for 85 hp, and later upped to 120-150 hp.
A new transom would allow for a great many options for power, both vintage and modern, plus you'd have the assurance of adequate transom strength.

Ques ca se ya'll need a new transom in Francais. It's not a Faux Pas. Like your comment about everything about the ability to float
I had a couple of them. If you install a new 20" transom your search for power would be much more fruitful. There are threads here with great "how to" steps on putting one in and I'm sure you'll have some good advice.
.....Oh ya, Welcome to the group.

What is the generic name for the Catalina boat style? Cabin cruiser? I think I need one.

Dave, they're fondly called pocket cruisers.

Bob

I think this what you need...the ultimate pocket cruiser. Notice that the design allows for zero wasted space, unlike what you normally find in traditional hull construction. Also, the bow drops down for amphibious assaults on tropical beachheads or smuggling illegals across the Rio Grande. Paint is optional.