Pros N Cons Cat 27 Inboard vs Outboard

caguy · Dec 11, 2012

When I bought my boat it had been halfway sunk for a few months. The IB motor was toast. It was a 2 stroke with a saildrive. When I bought it I figured if the motor could not be repaired I would replace it with an OB. I really wanted and electric start wand remote control since the old remote control was already in the cockpit. I found a 18hp Tohatsu that the guy bought new and only used once on a lake. It sat in his garage for 20 years on a stand under a blanket. He wanted $600 for it. It was beautiful. It was not electric start but that was fixable. I had to replace the fly wheel and buy a starter motor. I made the brackets. The motor runs like a dream and is easy to work on (not that I've had to do anything to it.) When I pulled out the old IB I remember thinking I'm glad I won't have to crawl in there again.
I haven't had any problems with cavitation even in high seas. In dead wind it pushes the boat along easily and efficiently at 5.5 kts. If I open it up I can get just over 7 kts. Usually I throttle forward on it just enough to engage the tranny and at that low idle I can still maintain 5-6 knots with the sails up and very little wind.
The boat came with a 12 gallon tank that leaked on the way home from PA. I replaced it with a 9 gallon plastic tank that lasted me most of the year.
For lake sailing I would have no problem with a OB just make sure you get a 4 stroke many lakes do not allow 2 strokes out here in the land of fruit and nuts.

trasel · Dec 24, 2012

Interesting topic...IMHO, 2 big factors to consider are 1- an outboard is much more maneuverable while steering in close quarters such as while docking single-handed plus 2- an outboard stretches your sailing season, as you don't have to winterize it.

trasel · Dec 24, 2012

I am currently using an 8hp Honda outboard and love it, however will reinstall my 11hp diesel inboard come springtime...thinking about keeping both engines on boat for awhile...does anyone know of any negatives to keeping both engines on boat?..it sure would be a nice redundant safety factor.

caguy · Dec 24, 2012

You can also use the same OB on your dink.

trasel · Dec 25, 2012

caguy said:
You can also use the same OB on your dink.

Yes, good point, however my 8' fiberglass dink is only rated for 2-3 hp

Joel H. · Dec 25, 2012

trasel said:
Interesting topic...IMHO, 2 big factors to consider are 1- an outboard is much more maneuverable while steering in close quarters such as while docking single-handed plus 2- an outboard stretches your sailing season, as you don't have to winterize it.

I've never handled a outboard on a sailboat so this is a sincere question.

An outboard is more maneuverable?

I would have thought the opposite! I mean my prop. is right in front of the rudder and my C27 will almost turn circles in it's own footprint...Almost, I say.

caguy · Dec 25, 2012

Joel H. said:
I've never handled a outboard on a sailboat so this is a sincere question.

An outboard is more maneuverable?

I would have thought the opposite! I mean my prop. is right in front of the rudder and my C27 will almost turn circles in it's own footprint...Almost, I say.

What he means is that you can asssist steering by turning the motor. It's pretty difficult with a C27 because it sit so low on the transom. I used it the other day when I needed to back out of a tight spot but could not get steerage with out some speed. So I tweeked the motor a little and got the boat turning.

Joel H. · Dec 26, 2012

I see

FourPoints · Dec 26, 2012

trasel said:
an outboard stretches your sailing season, as you don't have to winterize it.

NOT TRUE!!!!

While the procedure is simple, it is still very important that you properly winterize an outboard. Failure to change the lower unit gearcase oil results in many destroyed lower units each winter. If there is a small amount of water that gets in past the seals over the summer season (not uncommon, especially in older engines), that water will seperate from the oil (it's usually pretty emulsiphied) and can cause rust which will over time destroy the gears, or worse, if enough water gets in, it will expand and burst the lower unit when it freezes.

You also need to run the engine out of gas / drain the carb, fog the cylinders (not required, still a good idea on 4 stroke), and make sure all the water is out of the engine and exhaust leg.

This whole process generally takes about an hour.

Spring commissioning on an outboard is even simpler, drop the exhaust leg and put a new water pump impeller in, reinstall the exhaust leg, start the engine and let it burn off the fogging oil. If you have done it before, changing an impeller takes about 20 minutes. The impeller can be changed every 2 years if you don't run the engine a ton, you should never exceed 3 years (the rubber gets brittle and could break off).

trasel · Dec 26, 2012

About winterizing an outboard; This is my 1st yr w/ outboard and I have been using it weekly since Feb...guess I rec'd incorrect info from PO about winterizing...my bad, as I certainly don't want to give incorrect info to anyone...anyway, thanks for correction, think I will go down and rescue my outboard off of my transom asap...sorry for my unintentional incorrect info on winterizing outboards.

philwsailz · Dec 26, 2012

Winterizing an outboard is only necessary if you are laying it up for a long period. For several years recently, I sailed every month, even through freezing. If your lower unit is sealed, no need to worry.

The way to check lower unit for water is let it sit a while. It settles out water from oil if there is any. If the motor has already been sitting, 3 or 4 days, crack open your lower lube screw. If water comes out first, you have an issue. If clean gear oil comes out, zero issue. If you are in a hurry, crack open the screw right away if the oil is milky, it has water it in. If clear, no water.

Assuming nothing but oil comes out of the lower unit, and assuming you are going to use the boat every two or three weeks, even over the winter, just run it like you do in the summer.

Think about all the outboard-powered fishing and duck boats that are out all winter long......

trasel · Dec 26, 2012

Thank you for clearing up this issue a little more as I was intending on boating regularly through this winter...however now, Instead of removing my OB this week, I will just check for water in gear oil as previous post recommended...thanks again!

FourPoints · Dec 26, 2012

philwsailz said:
Winterizing an outboard is only necessary if you are laying it up for a long period. For several years recently, I sailed every month, even through freezing. If your lower unit is sealed, no need to worry.

The way to check lower unit for water is let it sit a while. It settles out water from oil if there is any. If the motor has already been sitting, 3 or 4 days, crack open your lower lube screw. If water comes out first, you have an issue. If clean gear oil comes out, zero issue. If you are in a hurry, crack open the screw right away if the oil is milky, it has water it in. If clear, no water.

Assuming nothing but oil comes out of the lower unit, and assuming you are going to use the boat every two or three weeks, even over the winter, just run it like you do in the summer.

Think about all the outboard-powered fishing and duck boats that are out all winter long......

Correct, but the lower unit oil should still be changed annually, even if you don't see any water in it.

trasel · Dec 26, 2012

My transom mounted OB gear oil drain screw (the lower one, right?) is just barely below water level when motor is in vertical position. Can I still unloosen screw for water check test in any of the 3 tilt positions on 08' 8hp Honda 4stroke?

NC-C320 · Dec 26, 2012

A sea story...actually a river story. Years ago, I had just ordered a new Kells 28 and specified an outboard mount for which I would add the outboard when boat was delivered. The idea was that the outboard would be cheaper than the inboard. At a July 4th event just after placing the order, there were lots of boats tied up against an exposed seawall. A thunderstorm came up and the water began to get choppy, with the boats taking a beating against the seawall. One by one, they began to move to a better location. A Cape Dory 25 or 26 with outboard tried to get underway. Lots of attempts with no success, but he needed to move. The problem was that the outboard engine prop was popping out of the water and engine would overrev, but could never get enough bite to push the boat off against the waves and wind. Someone with an Islander 28 and inboard diesel pulled along side the Cape Dory, secured lines to it with fenders between to protect the boats. And with no strain at all, moved both boats to safety. For me, that was convincing. The following work day, I called the manufacturer and said forget the outboard mount, put in the inboard diesel. Never regretted going the diesel route.

philwsailz · Dec 26, 2012

FourPoints said:
Correct, but the lower unit oil should still be changed annually, even if you don't see any water in it.

Part of a good annual habit, but not always necessary. It is quite possible to run an outboard many seasons without changing LU lube if no issues are found on routine inspection. Many LU drain screws have magnets on them to catch wear material. If an annual inspection shows no steel shavings, i.e. wear material, the oil is usually good for another year. Clean 90wt. will last a long time if nothing is wrong with the motor.

Again, when flying blind it is best to err on the side of caution, so your advice is solid for the average joe who is afraid to asses oil condition on his own, but as a hobbyist outboard repair guy I can tell you a clean lower unit needs only to be sealed quickly back up and used for another year.

FourPoints · Dec 27, 2012

philwsailz said:
Part of a good annual habit, but not always necessary. It is quite possible to run an outboard many seasons without changing LU lube if no issues are found on routine inspection. Many LU drain screws have magnets on them to catch wear material. If an annual inspection shows no steel shavings, i.e. wear material, the oil is usually good for another year. Clean 90wt. will last a long time if nothing is wrong with the motor.

Again, when flying blind it is best to err on the side of caution, so your advice is solid for the average joe who is afraid to asses oil condition on his own, but as a hobbyist outboard repair guy I can tell you a clean lower unit needs only to be sealed quickly back up and used for another year.

While I don't disagree, I won't go so far as to say I agree. My Dad owned an outboard repair business for a number of years when I was growing up, and I spent my summers as a kid changing water pumps, changing gear case oil, and helping rebuild engines.

I know what good lower unit oil looks, smells, feels, and yes even tastes like. After a season of heavy use, even if the lower unit didn't leak one drop of water, the oil still has a different smell and feel to it. I don't know why, but something in it (probably an anti-corrosion additive or something like that) most certainly breaks down with use.

After a season of heavy use, it's still oil, and it's still lubricating, but it's not quite the same as what you put in originally. I don't know what is changing to say if it is really less effective or not, but I do know this.... My first car was paid for by people not checking and changing their lower unit oil often enough.

caguy · Dec 27, 2012

FourPoints said:
While I don't disagree, I won't go so far as to say I agree. My Dad owned an outboard repair business for a number of years when I was growing up, and I spent my summers as a kid changing water pumps, changing gear case oil, and helping rebuild engines.

I know what good lower unit oil looks, smells, feels, and yes even tastes like. After a season of heavy use, even if the lower unit didn't leak one drop of water, the oil still has a different smell and feel to it. I don't know why, but something in it (probably an anti-corrosion additive or something like that) most certainly breaks down with use.

After a season of heavy use, it's still oil, and it's still lubricating, but it's not quite the same as what you put in originally. I don't know what is changing to say if it is really less effective or not, but I do know this.... My first car was paid for by people not checking and changing their lower unit oil often enough.

Do you have a brand of oil you recommend?

philwsailz · Dec 27, 2012

FourPoints said:
While I don't disagree, I won't go so far as to say I agree. My Dad owned an outboard repair business for a number of years when I was growing up, and I spent my summers as a kid changing water pumps, changing gear case oil, and helping rebuild engines.

I know what good lower unit oil looks, smells, feels, and yes even tastes like. After a season of heavy use, even if the lower unit didn't leak one drop of water, the oil still has a different smell and feel to it. I don't know why, but something in it (probably an anti-corrosion additive or something like that) most certainly breaks down with use.

After a season of heavy use, it's still oil, and it's still lubricating, but it's not quite the same as what you put in originally. I don't know what is changing to say if it is really less effective or not, but I do know this.... My first car was paid for by people not checking and changing their lower unit oil often enough.

Good old black dead-dinosaur and prehistoric-fern-based 90 wt Hypoid oil certainly has a unique smell. I won't argue that!

Mine is not a blind recommendation from a consumer, but rather it is based on extensive outboard maintenance knowledge as a hobbyist vintage motor mechanic. I can tell you off the top of my head that it takes a 9/16 wrench and a 7/16 wrench to drop an older OMC lower unit, after looosening the fine-thread bolts under the shift shaft cover with a 3/8 wrench...

But that's not important right now.....

I do know today's lubricants are significantly better than they were "back in the day". My 50's era outboard motors were designed to be mixed 24:1 with 30WT automotive oil. Today we use TCW3 as a better lower-carbon-fouling substitute, (still 24:1, I don't like rebuilding power heads and oils is relatively cheap). Many LU lubes are now synthetic, and are certainly multi-season. I would suspect that a 2008 Honda probably has synthetic in it. just a hunch, I have not searched it yet.

I have to consider your comment in context. Your example points to a season of heavy use. My little vintage runabout's '57 Johnson got drained and refilled every year, because I used it a lot. I mean like every weekend for several years until I finally put it in the shop and covered it up. On that point, you and I are on the totally same page.

Considering the light duty asked of an outboard sailboat auxiliary though, I have no problem at all recommending that LU lube can go two or more seasons, assuming the motor has not been punished, there is no excess of wear metal, and the lube is dry and the same color as when it was first put in. If it has browned or darkened appreciably, as that is a visual clue that there is a need to change it.

I highly recommend routine and proper maintenance. It is a good habit, and breeds other good habits. I just want to stop short of making a statement that can be perceived as a scare tactic that causes someone who is not as familiar with a topic to fear for the worse...