Outboards vs Stern Drive (Mercruiser)

[Nomad57]

Back in the 1970s, I had a serious case of footitis. I bought my first boat in 1975 with an outboard, but after taking it to a "rock concert" by the second weekend, (and getting towed back by a boat that had a stern drive) I fell in love with the quiet operation, and soon moved on to stern drives. I traded every year or two, so I never kept any boat long enough for the troubles to start.

Of late, I've been reading in this forum some posts that debate Johnrude vs Mercury, and it seems they both had some issues back then. It made me wonder if the stern drives were any better over the long haul. (By this I mean reliability-wise.)

Any thoughts on this?

 

[DJ]

Re: Outboards vs Stern Drive (Mercruiser)

This is a completely "personal preference" question. Several things to consider.

1. Outboards (pounds v. performance) outclass sterndrives hands down.

2. Either is only as good as it has been maintained. I've towed many sterndrives.

3. Aesthetics. Some like the smooth lines of a Sterndrive. Not to be sexist, but women especially.

4. Stern drives require a great deal more maintenance than outboards See below.

a. Lower gearcase (same as outboards).

b. Upper gearcase-Outboards don't have one.

c. Exhaust bellows-Not on OB's.

d. Exhaust manifolds/risers-Not on OB's.

e. Gimbal bearings-not on OB's.

f. Engine oil changes. That one could be a wash, assuming you are looking at four stroke outboards.

g. Winterizing: OB's (run some fuel conditioner throught it, change the Lower Unit lube-DONE.

I/O's-lube the gimbal bearing, drain the L/U and upper, drain and refill the oil+filter, run fuel conditioner through. MAYBE-check engine to outdrive alignment.

Those are just a few.

Plus, I/O's are a LOT heavier (typically). If you are marginal on your tow vehicle for an OB, you are overloaed with an I/O.

It's all personal choice.

 

[Nomad57]

Re: Outboards vs Stern Drive (Mercruiser)

DJ,

Thanks for your response, but I was aware of most of that. I ought to have emphasized, I was asking mainly about reliability of one versus the other. I should clarify: The reason I asked this, was that the Johnrudes of that era had the hydro-mechanical shift, which has been a problem, and the Mercs had other issues (especially the inline sixes, not as many seem to have survived to this day).

I just wondered if the stern drives of that era were more reliable than the outboards of that era.

Thanks again for the reply.

Nomad

 

[Silvertip]

Re: Outboards vs Stern Drive (Mercruiser)

Reliability is directly related to preventive maintenance and owner awareness. Outboards and stern drives don't die -- their owners "kill" them. They do this by not paying attention to the little things that can turn out to be big things. They do not understand what damage lean carburetion can do to an engine so they continue to run it until there a major issue develops. They don't winterize properly or at all when required. Annual maintenance to some consists of "lets see if it starts! Yup -- good to go!" Stern drive owners have a segement of their ranks that have no idea what goes on under the engine cover either. They never check engine oil so they have no idea if it is becoming fuel contaminated, water contaminated, or simply low even though the oil pressure gauge is telling them things aren't right. Or they have an overheat and insist on running many miles back to the dock destroying the engine in the process. Yes -- there are some years where powerplants had some "potential" problems. Owners that recognized a symptom got the engine fixed promptly (generally under warranty). Those that ignored subtle little things suffer the consequences. Understanding the requirements of your power plant goes a long way towards ensuring the rig stays reliable.

 

[DJ]

Re: Outboards vs Stern Drive (Mercruiser)

Johnrudes of that era had the hydro-mechanical shift, which has been a problem,

I disagree. The electro mechanical shifts were troublesome but they disappeared in '72'. The I/O's use an almost identical shift system as todays outboards. Volvo has the best acting and most reliable, IMHO.

An I/O maintained perfectly might see 2500 hours. Others will debate that. Our 2000 Merc. 75 HP (2 stroke) has way over that. A little 3 HP Evin. I have probably has at least that.

As eluded to by Silvertip. I can kill either inside one hour. It's completely the owners responsibilty when it comes to engine life. Both are capable of providing PLENTY. However, when it comes to simplicity. The OB wins.

 

[mnypitboat]

Re: Outboards vs Stern Drive (Mercruiser)

It seems to be all a matter of opinion around here. Some say an O/B is easier to maintain, some say an I/O is. Both are engines, both had drives. There are a couple things on each that the other doesnt have. An I/O is pretty easy to maintain. I change my oil 2 times a season and once in the winter. Same with my water seperator/filter. There is no winterizing here in FL, so that is not an issue. I change the outdrive oil once a year, and inspect it every time I change the engine oil. Bellows get inspected in Spring, and thus far they are origional and its an 01. My engine was absolutely NOT maintained before I got it, and I still got several seasons and hundreds and hundreds of hours. A lot of which was pushing it hard. I blew a headgasket this past spring and instead of messing with rebuilding my engine, I dropped another engine in there. So I still have the origional engine to rebuild for next time.

Thus far, I probably do not have $2000 total in that engine, and that includes a new engine this year. Most of the rest has been rusted parts from the previous owners neglect. Distributor was rotted, power steering resevoir, trim solonoids, starter. All rust related. I will not have this issue again. I am a wacko about maintainance.

 

[DJ]

Re: Outboards vs Stern Drive (Mercruiser)

It seems to be all a matter of opinion around here. Some say an O/B is easier to maintain, some say an I/O is. Both are engines, both had drives. There are a couple things on each that the other doesnt have. An I/O is pretty easy to maintain. I change my oil 2 times a season and once in the winter. Same with my water seperator/filter. There is no winterizing here in FL, so that is not an issue. I change the outdrive oil once a year, and inspect it every time I change the engine oil. Bellows get inspected in Spring, and thus far they are origional and its an 01. My engine was absolutely NOT maintained before I got it, and I still got several seasons and hundreds and hundreds of hours. A lot of which was pushing it hard. I blew a headgasket this past spring and instead of messing with rebuilding my engine, I dropped another engine in there. So I still have the origional engine to rebuild for next time.

Thus far, I probably do not have $2000 total in that engine, and that includes a new engine this year. Most of the rest has been rusted parts from the previous owners neglect. Distributor was rotted, power steering resevoir, trim solonoids, starter. All rust related. I will not have this issue again. I am a wacko about maintainance.

I think that settles it.

 

[jonesg]

Re: Outboards vs Stern Drive (Mercruiser)

I installed my 150hp jonny outboard myself and it was simple, when someone says they "dropped a new engine in" I have to wonder.
Its a bit more involved than an outboard.

One thing for sure, this website makes it all possible for many of us, otherwise it would be unthinkable. Theres no way I could afford to have a mechanic do what I've done.

 

[Nomad57]

Re: Outboards vs Stern Drive (Mercruiser)

I appreciate the responses, but when someone tells me that engine life is dependent upon maintenance, they may as well tell me that the sky is blue, except on cloudy days. That kind of response does not answer the question as to whether or not I/Os of the '70s had fewer or more problems than O/Bs of that era. That engine life is dependent on good maintenance is a given. I've seen the results of neglect, which is one reason why I bought all of my boats new except for one (It was a direct-drive inboard, which gave no problems except for the usual maintenance).

I suppose if I were to ask the same question in the I/O forum, I might well get different answers.

Thanks again, for all of your responses.

Nomad

 

[ezmobee]

Re: Outboards vs Stern Drive (Mercruiser)

In general....outboard motors a more complicated. They usually have multiple carbs and more complex ignition systems. However, I/O's have a whole lot more mechanics between the motor and the prop. So it's kinda a wash.

I think the reliability of a NEW outboard compared to a NEW I/O from any era is comparable.

However, if I'm going to choose between a used outboard or a used I/O, I'll take the outboard every time. Catching up on deferred maintainence on an I/O is costly and requires skills I don't have to DIY.

I am personally not an I/O fan at all....to the point that if someone gave me one for free I would immediately sell it.

 

[Nomad57]

Re: Outboards vs Stern Drive (Mercruiser)

Ezmobee,

I understand your feelings on the subject. I realize that there is a whole lot more to an I/O. I became a fan because of the sound level and timbre. In 1975 I bought a Merc 50, in part because of what I read in Consumer Reports. If I had it to do over again, I would have taken the Johnson 50, as I believe that they were not as noisy with the fibreglass shroud. The sound of the Merc bothered me, since I almost always boated with the top and side-curtains up. The Mercruiser 165 was much easier on the ears. In a 17' boat, though, an outboard would have made more sense. I didn't want the inline six O/B, and I didn't want the OMC shift. I was not then aware of the difference between the hydro-electric and the hydro-mechanical shift, it was all bad to me.

A wise old geezer at the time told me that he would not have an I/O in any boat under 20 feet, and looking back, it was good advice. In my neck of the woods, at the time, as soon as they hit about 19', they had I/Os.

Regards,

Nomad

 

[mnypitboat]

Re: Outboards vs Stern Drive (Mercruiser)

I think that settles it.

What is that supposed to mean?? I simply gave him my experiance. Since I have never owned an O/B, so I cannot give any info on that. The I/O is easy to work on, cheap to maintain, and other than a previous owner's lack of maintainance, I have really not had a ton of issues. And its 10 years old now with a ton of hours. I figure this thing got a good 5 years with zero money spent on maintanance before I got it. I think I am way ahead of the game.

Installing the engine was the only really tough part, and that was only because I didnt have a tall enough tree to hook a come-along to. I had to rent a tow truck. It was pretty simple and straight forward though. Much easier than the engine I installed in my Camaro the year before.

 

[jeffersondodson561]

Re: Outboards vs Stern Drive (Mercruiser)

Not to mention that the outboard manufactures cast their own blocks unlike Sterndrive that buy their blocks from GM or Ford. Remember how the 5.7 was so universal and the standard of the V8, well now technology can gernerate more horsepower from smaller cubic inches and the boating group is not enough to keep any manufacturer in business. So outboards may be the last survivors in this global market recession.

 

[Nomad57]

Re: Outboards vs Stern Drive (Mercruiser)

An I/O maintained perfectly might see 2500 hours. Others will debate that. Our 2000 Merc. 75 HP (2 stroke) has way over that. A little 3 HP Evin. I have probably has at least that.

That is an amazing revelation to me. I had always believed that O/Bs were 1,000 hour engines (a belief that dates back to the 1970s, based upon info that was available to me at that time). I do understand that there have been significant improvements to O/Bs since the 1970s, and consider it possible that an engine from the year 2000 can be more durable than one from the 1970s, but am doubtful that one from that era could have managed 2500 hours or more. (I once saw an O/B of 45 hp that was six years old. A look inside the cylinders gave me the impression that it was ready for the bone heap.)

I do have to ask, though, how you managed to put 'way over that' (2500 hours) on a motor in ten years. Truth be told, I have never seen an hour meter on an O/B. I wonder how you tallied the hours.

Regards,

Nomad

 

[dingbat]

Re: Outboards vs Stern Drive (Mercruiser)

That is an amazing revelation to me. I had always believed that O/Bs were 1,000 hour engines (a belief that dates back to the 1970s, based upon info that was available to me at that time). I do understand that there have been significant improvements to O/Bs since the 1970s, and consider it possible that an engine from the year 2000 can be more durable than one from the 1970s, but am doubtful that one from that era could have managed 2500 hours or more. (I once saw an O/B of 45 hp that was six years old. A look inside the cylinders gave me the impression that it was ready for the bone heap.)

I do have to ask, though, how you managed to put 'way over that' (2500 hours) on a motor in ten years. Truth be told, I have never seen an hour meter on an O/B. I wonder how you tallied the hours.

Regards,

Nomad

Well, it?s pretty easy. You run the boat 8-10 hours a day instead of letting it sit 6 months out of the year.

My 1997 Evinrude 200HP has well over 2,000 hours on it. I put 127 documented hours in April alone. Put another 50-60 hours in May. It is going back in the slip on Monday and I'll probably put another 50-60 hours on it before I put the cover it in January.

A lot of my friends use their boats commerically. Putting 3000 - 3500 hours on an outboard between rebuilds is not unheard of.

 

[WIMUSKY]

Re: Outboards vs Stern Drive (Mercruiser)

I have both, or should I say had(I just sold my 24'), I would take an outboard. To me, they seem to be alot less hassle and less issues.....JMO

 

[skargo]

Re: Outboards vs Stern Drive (Mercruiser)

Considering what forum this was posted in, the replies are very predictable.

 

[Nomad57]

Re: Outboards vs Stern Drive (Mercruiser)

My bad. I was brand new to the forum, it was my first post. I posted there, because that's where I had read about some of the O/B issues.

Nomad

 

[jeffersondodson561]

Re: Outboards vs Stern Drive (Mercruiser)

Well, it?s pretty easy. You run the boat 8-10 hours a day instead of letting it sit 6 months out of the year.

My 1997 Evinrude 200HP has well over 2,000 hours on it. I put 127 documented hours in April alone. Put another 50-60 hours in May. It is going back in the slip on Monday and I'll probably put another 50-60 hours on it before I put the cover it in January.

A lot of my friends use their boats commerically. Putting 3000 - 3500 hours on an outboard between rebuilds is not unheard of.

Agreed! It so hard to convince someone that the worst thing you can do to an engine is let it sit.

 

[JBF 1962]

Re: Outboards vs Stern Drive (Mercruiser)

my last boat was a 1978 with a 165hp mercruiser and in the 8 years that i had it, was totally reliable unlike the 1975 Evinrude 70hp I had before that. Of the 70's i/o's I've come to know, those that are OMC's n Volvos seem to be nightmares...nasty looking units at that, lol