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I/O OR OUTBOARD - WHAT'S BEST??

Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

I/O OR OUTBOARD - WHAT'S BEST??

On Sat, 06 Sep 2003 16:32:35 GMT, "-v-" wrote:

"Jim Stallings" wrote in message
. com...
Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

1) Outboards are much lighter than IO's for a given horsepower.
2) Outboards are simpler than IO's. No U-Joints and bellows seals.
3) Outboards don't require a big hole in the transom.
4) Maintenance is easier on an outboard since the whole engined is out in
the open where it can be reached for service. You will appreciate this the
first time you have to lay on your back and hug an engine block in the bilge
of your boat to reach something that needs fixing.
5) There is less maintenance on an outboard since they are simpler.
6) Outboards were designed from scratch as marine engines and are not
converted car/truck engines thus they are much more durable in a sal****er
environment.
7) Outboards greatly reduce, if not entirely eliminate, the threat of
fire/explosion from gas fumes in the bilge.
8) Outboards can be tilted clear of the water if the boat is kept in the
water. Stern drives can't. This reduces corrosion and marine growth. Keeping
the boat on a boat lift or trailer is better.

I have an I/O now, Mercruiser 5.7L with an Alpha 1 drive. I will go for an
outboard next time.

John
On the 'Poco Loco' out of Deale, MD

I/O OR OUTBOARD - WHAT'S BEST??

Well ... if I had the bucks I'd have gone 4 stroke outboard ... the I/O
takes up a lotta floor space, the whole system (motor, outdrive, bellows
etc) is complex, it's way heavy, and it's "firmly attached" to the boat as
in you're not likely gonna upgrade one or the other independently as you can
with an outboard.

So if you're going fishing, skiing with a 17' boat and plan to take along a
coupla friends, go outboard so there's some elbow room ... imho.

"-v-" wrote in message
m...

"Jim Stallings" wrote in message
om...
Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

1) Outboards are much lighter than IO's for a given horsepower.
2) Outboards are simpler than IO's. No U-Joints and bellows seals.
3) Outboards don't require a big hole in the transom.
4) Maintenance is easier on an outboard since the whole engined is out in
the open where it can be reached for service. You will appreciate this the
first time you have to lay on your back and hug an engine block in the
bilge
of your boat to reach something that needs fixing.
5) There is less maintenance on an outboard since they are simpler.
6) Outboards were designed from scratch as marine engines and are not
converted car/truck engines thus they are much more durable in a sal****er
environment.
7) Outboards greatly reduce, if not entirely eliminate, the threat of
fire/explosion from gas fumes in the bilge.
8) Outboards can be tilted clear of the water if the boat is kept in the
water. Stern drives can't. This reduces corrosion and marine growth.
Keeping
the boat on a boat lift or trailer is better.

I/O OR OUTBOARD - WHAT'S BEST??

"Jim Stallings" wrote in message
om...
Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Actually, it's not obvious and is really an individual decision based on
your particular plans. My comments below are based on my recent personal
experience going from a Chevy block inboard jet configuration (similar in a
lot of ways to an I/O) to a large V-6 outboard.

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

"-v-" wrote in response

1) Outboards are much lighter than IO's for a given horsepower.

I Agree

2) Outboards are simpler than IO's. No U-Joints and bellows seals.

Don't know/no experience with outdrives.

3) Outboards don't require a big hole in the transom.

True, but I've never heard of transom leaks being a significant problem in
my little world. My inboard jet, with a big hole in the transom, never had
a problem, nor did the people I knew with that set up.

Counterbalanced, I would say, by the way an inboard block sits on the
internal bottom structure of the boat rather than hanging on the transom.

4) Maintenance is easier on an outboard since the whole engined is out in
the open where it can be reached for service. You will appreciate this the
first time you have to lay on your back and hug an engine block in the
bilge
of your boat to reach something that needs fixing.

5) There is less maintenance on an outboard since they are simpler.

These are probably true. Basic outboard maintenance is really simple.
Changing the oil, plugs and filters on an inboard engine can be a PITA, but
not that big of a deal. I don't really know about outdrive maintenance, but
outboard lower unit maintenance is really simple as well. But, I only do
the very basic maintenance on my engines and haven't seen either to be a
huge problem. Some people really like the inboard engines better for
whatever reasons.

6) Outboards were designed from scratch as marine engines and are not
converted car/truck engines thus they are much more durable in a sal****er
environment.

Don't know how significant this is (do sal****er only sporadically). Don't
think it's a huge factor in fresh water though.

7) Outboards greatly reduce, if not entirely eliminate, the threat of
fire/explosion from gas fumes in the bilge.

Agree.

8) Outboards can be tilted clear of the water if the boat is kept in the
water. Stern drives can't. This reduces corrosion and marine growth.
Keeping
the boat on a boat lift or trailer is better.

Agree - but as you said, a trailered I/O probably works OK in salt water as
well.

Don't forget that the outboard takes up [virtually] no interior space - this
can be very important in a 17-19 foot boat.

I would say outboards cost quite a bit more / horsepower than I/Os?

Gas mileage and water and air pollution were/are a major downfall of
outboards vs. I/O. I don't really know how modern 4 strokes and/or DFI or
EFI 2 strokes compare to an I/O, but I imagine they've narrowed the gap a
lot - maybe totally?

I went to my current outboard set up (over previous inboard jet, similar to
an I/O) because of the weight and interior space factors - they were *the*
important factors for me for the type of boating I do. I do NOT like the
fuel economy factor. I'd switch to a modern fuel inj. two stroke or four
stroke, but I do NOT like the cost / horsepower factor in doing that! I can
buy a lot of gas for the cost it would take to replace the outboard. (But
will do it when I need to).

I liked my old inboard jet because the engine gave me much more HP for the
money, was much cheaper to rebuild and/or replace (the engine, that is) and
was very similar (and therefore understandable to me) to the Chevy engine in
my pickup. Fuel mileage was far, far better than old carbureted 2 stroke
outboard. But the weight and interior space required in a 20 foot boat were
just too much.

So, to the original poster, in my opinion, there's no "correct" answer - it
depends on how these factors weigh in for you. I strongly recommend you try
to simulate or at least imagine how the interior space of I/O vs. outboard
will work for you in the activities you will be doing. Definitely spend
some time inside of boats you're looking at.

DJ

I/O OR OUTBOARD - WHAT'S BEST??

DJ wrote:

5) There is less maintenance on an outboard since they are simpler.

These are probably true. Basic outboard maintenance is really simple.
Changing the oil, plugs and filters on an inboard engine can be a PITA, but
not that big of a deal. I don't really know about outdrive maintenance, but
outboard lower unit maintenance is really simple as well. But, I only do
the very basic maintenance on my engines and haven't seen either to be a
huge problem. Some people really like the inboard engines better for
whatever reasons.

Well, I'm a fan of outboards, as opposed to I/O's, but modern high
horsepower outboards for the most part are not simple engines a decent
backyard mechanic can maintain or repair. The simple maintenance items
on an outboard engine or a car engine are probably a wash.

6) Outboards were designed from scratch as marine engines and are not
converted car/truck engines thus they are much more durable in a sal****er
environment.

Some outboard engines are designed from scratch as marine engines.
Others are based on car engines. The larger Hondas have car engine origins.

--
* * *
email sent to will *never* get to me.

I/O OR OUTBOARD - WHAT'S BEST??

Everyone --

Wow! Lots of benefits to outboards I hadn't known or thought about.
Thanks so much for your input. I was ready to write an OB out, but
now I'm going to look closer and really compare.

One thing that no one mentioned that I wonder about -- noise level.
Is either motor inherently quieter in most operation? How about the 4
stroke OBs?

Thanks again for your help !!

Jim

I/O OR OUTBOARD - WHAT'S BEST??

There are advantages, and disavantages, to either.

I, also, suggest trying each, and deciding on what you like best.

Try a google search on "rec.boats FAQ", without the quotes. There is
a comparison section in the FAQ.

Good luck,
noah

I/O OR OUTBOARD - WHAT'S BEST??

Outboard for Sal****er, either for freshwater.

--

Keith
__
God doesn't play dice. -- Albert Einstein
"Bill Andersen" wrote in message
news:sTm6b.49045$nf3.35797@fed1read07...
I chose an I/O when I bought my 19' boat for the same reason.
Outboards weigh less but I/Os are more fuel efficient. Because it's a
little
easier to access an outboard, it's rumored that maintenance service costs
less. I doubt it.

"Jim Stallings" wrote in message
om...
Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

I/O OR OUTBOARD - WHAT'S BEST??

/nods

-W

"-v-" wrote in message news:D_n6b.10073

1) Outboards are much lighter than IO's for a given horsepower.
2) Outboards are simpler than IO's. No U-Joints and bellows seals.
3) Outboards don't require a big hole in the transom.
4) Maintenance is easier on an outboard since the whole engined is out in
the open where it can be reached for service. You will appreciate this the
first time you have to lay on your back and hug an engine block in the
bilge
of your boat to reach something that needs fixing.
5) There is less maintenance on an outboard since they are simpler.
6) Outboards were designed from scratch as marine engines and are not
converted car/truck engines thus they are much more durable in a sal****er
environment.
7) Outboards greatly reduce, if not entirely eliminate, the threat of
fire/explosion from gas fumes in the bilge.
8) Outboards can be tilted clear of the water if the boat is kept in the
water. Stern drives can't. This reduces corrosion and marine growth.
Keeping
the boat on a boat lift or trailer is better.

I/O OR OUTBOARD - WHAT'S BEST??

"Dan J.S." wrote in message
...

"Jim Stallings" wrote in message
om...
Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

you can't buy a Japanese i/o - and the quality of ALL i/o engines is that
of
the 80s made U.S. cars. Unless you get into the higher end diesels, etc.

So for a small boat i recommend an outboard Honda.

GM makes great marine base inboard engines. Honda and Toyota can't really
match then for that.

I/O OR OUTBOARD - WHAT'S BEST??

JohnH wrote in message

Brad, Have you had the manifolds and risers looked at? I've had mine in the Bay
since 1997, had the manifolds and risers off two years ago, and am thinking of
doing it again, just to see if replacement is in order.

John
On the 'Poco Loco' out of Deale, MD

No John, I haven't. How big a job is that? When I told my local
marine mechanic about my concern, his advice to me was, as long as I
like the boat (I do) and have no burning desire to replace it (I
don't) just to keep doing what I've been doing, taking good care and
maintaining the engine, and not worry too much. Worst thing would be
that I'd eventually have to replace the manifolds; a big job, but not
a disaster.

How big a job was it to take them off to inspect? I assume you found
things to be OK?

Brad

I/O OR OUTBOARD - WHAT'S BEST??

-v- wrote:

"Tan PS" wrote in message
...

2 stroke outbd cost less than half of inbds,

2 stroke outboards cost more than similar powered gas IO's.
4 stroke outboards cost a lot more than similar powered gas IO's.

That's the problem with outboards. They're perfect for salt-water use
but the 2-strokes are loud, stinky and use more gas. The 4-strokes are
a dream (have you ever "heard" a Honda 4-stroke at no-wake speeds?
whisper quiet) but cost out the patoot!!! I have an old (1988)
Mercruiser I/O and I'm constantly at war with corrosion and barnicals on
the outdrive but it sure runs sweet - and was cheap!

I/O OR OUTBOARD - WHAT'S BEST??

"-v-" wrote in message om...

: 2 stroke outboards cost more than similar powered gas IO's.

Who makes a 2-stroke IO? No crap here, just genuine interest.
Dave

I/O OR OUTBOARD - WHAT'S BEST??

"-v-" wrote in message om...
:
: "David Ward" wrote in message
: k.net...
: "-v-" wrote in message
: om...
:
: : 2 stroke outboards cost more than similar powered gas IO's.
:
: Who makes a 2-stroke IO? No crap here, just genuine interest.
: Dave
:
:
:
:
: I think Bayliner had some hybrid based on an inboard mounted Force OB about
: 1989.
:
: Also remember that an offshore racing team in the 80's , Popeyes I think,
: ran a boat with multiple OB powerheads linked to some kind of outdrive.
:
:
I just had a vision of a 2-stroke V-8 IO - truly awful fuel consumption,
but *what a hole-shot!*

I/O OR OUTBOARD - WHAT'S BEST??

A couple of boats ago I had a 120 Mercuiser I/O that was 20 years old and
running well. When I sold it I reflected on the fact I'd never seen a 20 year
old 120hp outboard. Running or not. Given the cost of new motors, my latest
boats have been fresh water cooled Mercuiser I/Os.
I'm in San Diego, all salt water.
Best of luck.
Mike

I/O OR OUTBOARD - WHAT'S BEST??

Hi Jim,
Opinions, everyone has one! My opinion is outdrive are best used in
heavier boat applications. When in the size range you speak of, the
advantage of an outboard is not having to share your very limited deck
space with an engine compartment. I do recommend a 4 stroke outboard as
they are much quieter and fuel efficient then 2 strokes.

Outdrives are great for larger boats with v-8 engines.

Regards and luck,

Capt. Frank Hopkins

Jim Stallings wrote:

Hello All,

This will probably be a painfully obvious question for many of you,
but I wanted to get some advice and I'm a novice powerboater (plenty
of sailing experience though!!)

Anyway, I'm in the market for a small runabout boat - perhaps 17 to 19
foot. It's to be used in both fresh and salt water here in the NW USA.
I plan to pull skiers as well as just cruise and maybe fish.

My question is - what are the advantages of an I/O vs outboard, and
vice versa. I've been leaning toward an I/O, mostly from the
standpoint of noise, simplicity, and looks (no unsightly motor in the
way....). What are some other considerations I should be aware of or
take into account.

Thanks VERY much for any help you can provide.

Jim

Capt Frank Says:

I do recommend a 4 stroke outboard as
they are much quieter and fuel efficient then 2 strokes.

Not necessarily so. Read below.....

Two-stroke Conventional Wisdom
BY RALPH LAMBRECHT

Everyone in the marine industry and most of its environmental critics are aware
that there are now at least four manufacturers of two-cycle outboards with DFI,
direct fuel injection: systems that put the fuel directly into the combustion
chamber after the intake and exhaust ports close. Such systems eliminate loss
of some of the incoming fuel charge out the exhaust ports along with the
scavenged products of combustion that occurs with carbureted or EFI manifold
injection systems. Nevertheless, conventional wisdom tells most of the critics
of the two-cycle engine that it will never be as clean as a four-cycle engine.
For this reason they would eventually advocate banning the two-cycle engine
from the waterways on environmental protection grounds.

There are even more manufacturers producing four-cycle outboards, including the
same manufacturers that make the DFI two-cycle engines. They must seemingly
follow down both roads for self preservation, as part of the outboard market is
definitely leaning in the four-cycle direction, driven that way by hype,
environmental concerns, and certain perceived advantages. We have already
considered the ramifications of the increased engine weight for the
four-cycles, the potential effect on boat trim, and the possible inability to
float the boat level when swamped, as required by federal regulations for
outboard boats less than 20-feet long. Then there is also the increased cost
and complexity involved with four-cycle power, to be offset by savings realized
in fuel consumed and elimination of smoke and oil slicks.

This may be the price of progress, they say. But, is it possible to "have your
cake and eat it, too?" Some recent tests run comparing 2002 model two-cycle DFI
outboards with four-cycle outboards of equal power rating, mounted on the same
boat, would seem to indicate such things are really possible. Comparison tests
of two brands of four-cycle 225-hp outboards were made with a current state-of
the-art DFI two-cycle 225. On identical 20'7" boats one four-cycle brand
produced a best mileage of 4.7 mpg at 27.7 mph while the two-cycle gave a best
4.5 mpg at 28.6 mph. Very close. But, the two-cycle had a top speed of 59.8 mph
against 52.4 mph for the four-cycle. At the same 52-mph speed the two-cycle
gave better mileage to the tune of 3.2 mpg to 2.7 mpg for the four-cycle. The
two-cycle produced better fuel mileage at every speed from 34 mph up and was
also better at trolling speeds of 4-7 mph.

When tested against the other 225-hp, four-cycle brand on identical 24' boats,
the DFI two-cycle again prevailed overall, delivering a matching best 3.15 mpg
at 32 mph. This outran the four-cycle 49.3 to 45.7 mph, getting better mileage
(2.58 mpg) at its top speed than the four-cycle (2.44 mpg) at its top speed. It
also produced far better mileage in the trolling speed range from 3.5-8 mph.

A third set of tests compared a 135-hp, two-cycle DFI outboard against a
130-hp, four-cycle outboard on identical 20' boats. The two-cycle delivered
4.25 mpg at 20.8 mph against a best 3.97 mpg at 20.4 mph for the four-cycle.
Best economy for the two-cycle was achieved at 27.9 mph: 4.45 mpg. It also
bested the four-cycle in the 3-8 mph trolling speed range and beat it in top
speed 43 mph/3.54 mpg to 37 mph/2.97 mpg.

"Bah, humbug!" you might say. But there are sound engineering internal
combustion engine principles for this surprising result. It is true that the
typical four-cycle engine may have an inherent advantage in fuel consumed per
horsepower. But not when the engine must be designed to produce very high
horsepower per cubic inch of displacement at high engine speeds, as it must to
achieve even the already heavier weight seen when compared to its two-cycle
competitor.

In order to achieve this high-power output, while firing only every other
revolution of the crankshaft, the camshaft valve timing must develop
considerable overlap between intake and exhaust valve openings and closings,
which means it begins to suffer some of the same raw fuel loss out the exhaust
problems as the carbureted or manifold injected two-cycle engine. It only has
manifold injection, so the fuel and air must mix in the manifold and enter
together past the intake valve into the combustion chamber while the exhaust
valve is still partly open. The result is Some loss in fuel economy.

Since the four-cycle engine has the same radical valve timing at low engine
speeds, it suffers even more when compared to the two-cycle DFI engine at
trolling speeds. The only way to fix this problem in the four-cycle engine is
to go to direct fuel injection into the combustion chamber after the valves
close, like the DFI two-cycle, or have a system providing variable valve timing
with engine speed, conservative timing at lower speed and radical timing at
higher speed. Such systems are now being developed for future automobile
engines. Such things would add complexity, cost and weight, to an already more
expensive and heavier product.

Then there is the factor of acceleration from idle to planing speed. On the 241
boat the 225-hp, two-cycle DFI went from zero to 150 feet in 7.06 seconds while
the four-cycle took 7.76 seconds. On the 20' boat the 135-hp, two-cycle DFI
went zero to 150 feet in 6.2 seconds while the four-cycle took 8.7 seconds for
the same distance. Acceleration from zero to 30 mph on the 20'7" boat for the
225-hp two-cycle DFI took 5.77 seconds compared to 10.7 seconds for the 225-hp
four cycle. This demonstrates the better low-end torque and fast-rising power
curve of the two-cycle, firing every revolution of the crankshaft. The
four-cycles are quieter at low engine speeds, but this advantage goes away at
the higher engine speeds.

So, the conclusions are that the state of the art two-cycle DFI outboard can
match or beat the four-cycle in fuel economy, top speed, and acceleration. What
about exhaust emissions, which brought on the whole move to four-cycle
outboards in the first place? These two-cycle engines can match or beat the
four-cycles there, as well. It matches pretty much with the fuel economy story.
The more fuel the engine consumes at a given boat speed, the more exhaust
emissions that come out the other end. With precise microprocessor control and
direct injection of the fuel into the combustion chamber after the ports close,
the two-cycle DFI can better the most stringent exhaust emission requirements
now proposed out to 2007. The four-cycle can do no better.

After more than five years of testing and field experience the 2002 two-cycle
DFI outboards have been developed to have quality durability, economy and
environmental friendliness to match or beat the four-cycles, and at lower
weight and cost. Both can exist and be successful in the marine market but no
one should sell the two-cycle engine short on its ability to survive and
prosper long into the future. It just has too many good things going for it.
You might even see it on some future stern drives.

Ralph Lambrecht is an engineer with more than 50 years of experience in the
marine industry and marine safety standards development.

Lambrecht, Ralph. 2002. â€œTwo-stroke conventional wisdom.â€? Boat & Motor
Dealer. April. 34-37

I/O OR OUTBOARD - WHAT'S BEST??

"F330 GT" wrote in message
...

I will go with the 4 stroke. As to complexity, when you start adding all
the DFI, etc, those 2 strokes become very complicated and the complication
is added by very precision parts. 4 storkes are the same complexity as
nearly every automotive gas engine built for the last 100 years. My problem
with the new clean burning 2 strokes is lubrication and cooling. 2 strokes
have always been lubed and some cooling by the incoming fuel / oil charge.
Now this fuel oil mixture is not there to lub the crankcase and cool the
piston internally. IMO is the reason for so many failures of the Ficht
(they got it really wrong and why the Optimax's are not living as long as
Clam's tower of power.
Bill