Pro/Con of outboard for blue water cruising

[GordMay]

Greetings and welcome aboard the CF, fitzdority.

[Hoosiersailor]

IMHO an outboard may be just right for a boat under 30' but do keep in mind that an inboard diesel usually does have a lot of advantages over an outboard including hot water, high amp alternator for power, more fuel efficient and overall it is going to be more reliable just by the more simple design.

Modern outboards really are great and on a small boat make a lot of sense. I had a 6hp motor on a Catalina that I would remove when anchored and put it on my inflatable dinghy. Really worked great.

[sailjumanji]

We have a 33 ft catamaran, with twin 9.9 hp high-thrust Yamahas. The original motors lasted over ten years, and around 2000 hrs. Would probably have gone more hours, but I suspect the first four years of life in charter service and Bimini runs from Miami (get there as fast as you can) probably put some extra stress on them. Anyway, when it came time to replace them, I just popped in two new motors in their place. I think cost was about $2k per motor. Good for another ten years and/or 2000-3000 hours of motoring. Push the boat at 7 knots at WOT, and 5-5.5 knots cruising at around 3500 RPM. At that speed, the 2012 model motors burn about 0.75 gal per hour total for the two. I usually budget about a gallon per hour. With tankage of 28 gals, that is a lot of motoring. Plus there is room to carry jugs onboard.

Both motors are electric start (pull start backup), with throttle and shift controls at the helm. With dual motors, the boat will just about turn a circle within its own length. We can motorsail with one engine. I have large canister filters on each. Maintenance is usually limited to oil changes, lower unit lube, water impeller replacements, and cleaning carbs on occasion. All of this is pretty easy. With care, you can pull the lower units from a dinghy or kayak. Or you can pull the entire engine using the boom overhead. (The latter taking more time as you have to disconnect the throttle and shift cables.)

I see Seawind now has a 38 ft Seawind 1160 Lite, that uses dual 30 hp (?) engines for propulsion. That would be my dream setup. Although my wife says I don't need a bigger boat. Will see if she says the same thing after we get back from our four-month planned cruise, coming up.

[thomm225]

Originally Posted by zeehag

one good sea over transom and no mas de outboard... might consider that, as often seas can be a nuisance while sailing em.

That's why it's good to have a smaller outboard.

Once ye clear the marina, entry channel, etc ye can relocate your outboard to the stern rail or some other good storage area. Ye could also drain the oil and wrap the motor in waterproof material and store near the bow.

[sailjumanji]

Oh, forgot the downsides. Cavitation or aeration. When motoring into really choppy seas and the boat starts hobby horsing, the prop can come close enough to the surface to aerate. It is quite annoying. I helped when I installed the power thruster - or whatever it is called - which is basically half-circle shaped stainless plating attached to the cav plate above the prop. It both redirects the prop thrust from up to back, but also provides a barrier from sucking air down to the prop in the event of hobby horsing.

Our outboards pull up into a cowling for sailing, with a single line. A Seawind stainless bracket. Am not sure how they could be flooded by a boarding sea. When we are sailing, the water flow and waves are generally going the other way. At anchor, waves on the bow. I guess if we ever got into a boarding sea situation, the outboards were not affected. After ten years of age, the heads and everything under the cowlings still looked pretty new. No real corrosion.

But if you put an outboard on the stern of a monohull, the hobby horsing could be a real issue. Our motors are between the hulls. probably about ten feet forward of the stern.

[Dave22q]

It really is not much of a choice. If your boat is under 30', intended usage is very limited as in entering/leaving harbor and you solve the problem of remote starting/throttle control; outboards are the way to go. If you carry a complete spare (overkill with a reasonably maintained motor) you will still have invested a small fraction of the cost of the cheapest diesel option. A long shaft 10 or 15 should do the job.

[hamburking]

Originally Posted by cruisersfarm

Times have changed.

New, fuel injected outboards sip fuel, especially as you back away from wide open throttle and into a steady cruising rpm.

30hp is a couple gallons an hour if not at 5000 rpm.

Compare that to a yanmar 2gm which uses about 1 litre per hour. The outboard is using 10 times the amount of fuel per hour. The yanmar 2gm replaced the 30hp atomic 4 on many sailboats. Also, a 30hp outboard is going to be a LOT of weight (and forces) on the transom.

[hamburking]

Generally, outboards make very few amps compared to an inboard engine. Unless you have a ton of solar panels, this is kind of a big deal for any kind of cruising.

[anacapaisland42]

Wow, my 35 year old Yamaha 9.9 has been in twice for service twice in that time, has driven thousands of miles in both salt and fresh water, has been frozen in ice 3 or 4 times, been used on boats from 15,000lbs to the Ribby
BUT I've always used premium gas (no ethanol) and AMSoil 2 stroke.

Bill

Originally Posted by Lepke

Outboards use lots of fuel. I'm 67 and been on the water since 7. In all that time except for diesel versions, I've never seen a reliable outboard.

[thomm225]

Originally Posted by hamburking

Compare that to a yanmar 2gm which uses about 1 litre per hour. The outboard is using 10 times the amount of fuel per hour. The yanmar 2gm replaced the 30hp atomic 4 on many sailboats. Also, a 30hp outboard is going to be a LOT of weight (and forces) on the transom.

A 30 hp isn't a good example for a sailboat that would normally use an outboard.

I have a 5hp 4 stroke and I can run for hours on a gallon of fuel. I have many times cross the lower Chesapeake and returned the 20 miles to my slip under outboard power which can take 3-5 hours (depending on tide, waves, and wind) with around a gallon or so of 10% ethanol fuel

[thomm225]

Originally Posted by hamburking

Generally, outboards make very few amps compared to an inboard engine. Unless you have a ton of solar panels, this is kind of a big deal for any kind of cruising.

I have a 100 watt solar panel in use and 40 watts of spares feeding two 12 volt batteries in parallel. This has worked fine for me during my vacation "cruises."

I also have no starter battery to worry about or remote control BS attached to the motor

[Shanachie]

I've owned outboard and inboard sailboats. There's no comparison. A diesel is so much better in so many ways.

Try muscling through a steep chop. It's hell on an outboard. Easy with a diesel.

Outboards can get swamped when running a rough East Coast inlet. It's very unnerving to lose your motor in a narrow, rock-lined channel with the wind on your nose. Been there. Didn't like it at all.

I once had an old Volvo outboard catch fire on me due to a leaky carb in the late '70s.

Diesels are much easier to work on than outboards. Especially if they don't have any electronics.

If you do go with an outboard, please remove the inboard and glass up the holes. There's no reason to sail a junk sailboat. Plus, you get plenty of storage space.

[Scaramanga F25]

The cost of you rebuilding the diesel should not cost more than a new outboard.
Outboards are extremely reliable if you have CLEAN no ethanol gas.

[thomm225]

Originally Posted by Scaramanga F25

Outboards are extremely reliable if you have CLEAN no ethanol gas.

Funny stuff!

My outboard loves it's old 10% ethanol gas.

I started my engine two weeks ago on the 10 % ethanol gas I bought in September. And in the Spring will use the rest of the fuel that is in the external tank also bought in September.

[ebsail]

I think you would have to have a sturdy and retractable motor mount. Really good ones (and as usual, buy one size larger than specified) cost upwards of $300 but allow you to get the engine high enough, about 15" higher out of the reach of the sea, than a fixed mount. When retracted and the engine tilted, the mount will eliminate all prop drag . Also keeps the prop clean. An extra long shaft is a must (25") to keep the prop in the water when the boat is pitching. A large propeller and a 4 cycle are a must

We now rarely sail in the Atlantic, and are working our way down to smaller boats as we age past 75, but our current O'day 25 does very well with a 6HP Tohatsu sail pro. A 3 gallon tank is good for about 6 hours. It also has a small alternator. Would have liked electric start but its not available on this model