Mercury 2-strokes' term of life

[dandreye]

Hi All,

What is the average actual term of life of Mercury 2-stroke outboards ever made?
Of course assuming careful operation and proper care i.e. never starting/running it
w/o oil, always using correct oil, never hitting any underwater obstacles etc. etc.

I do understand the question is too broad and general, so any replies are welcome.

My OB mechanic says 2-strokes last "only" 7000 hours, which would be perfect,
but other sources say 1500-2000 hours. Could the latter be the overhaul time
while the former be the time until powerhead replacement following two overhauls?
It'd also be great to know the overhaul time of the 2-strokes' lower units and
how many hours their particular subunits tend to last.


Many thanks in advance,

Dmitriy

 

[Bondo]

Re: Mercury 2-strokes' term of life

Hi All,

What is the average actual term of life of Mercury 2-stroke outboards ever made?
Of course assuming careful operation and proper care i.e. never starting/running it
w/o oil, always using correct oil, never hitting any underwater obstacles etc. etc.

I do understand the question is too broad and general, so any replies are welcome.

My OB mechanic says 2-strokes last "only" 7000 hours, which would be perfect,
but other sources say 1500-2000 hours. Could the latter be the overhaul time
while the former be the time until powerhead replacement following two overhauls?
It'd also be great to know the overhaul time of the 2-strokes' lower units and
how many hours their particular subunits tend to last.


Many thanks in advance,

Dmitriy

Ayuh,.... I think yer mechanic is dreamin',.... yer 2nd numbers are abit more realistic...

 

[wired247]

Re: Mercury 2-strokes' term of life

Ayuh,.... I think yer mechanic is dreamin',.... yer 2nd numbers are abit more realistic...

I dont know but I replaced the 90 Johnson on my 1981 Enticer last year just because I wanted a V6. My dad bought it in 1981 and it was the original powerhead. I had to replace the power packs and clean the carbs good from sitting for 7 years in the rain but it had cylinders that looked like new and still went 50+ MPH.

 

[dandreye]

Re: Mercury 2-strokes' term of life

Perhaps I got the figure of 7000 hours wrong myself though...

Let's put it this way then: which components in Mercury mid-hp range 2-strokes typically require overhaul or replacement upon reaching 2000 hours?

30 years is a quite encouraging figure especially with the cylinders in so good condition... assuming "average" 50 hours per year it gives 1500 hours total. Wondering if Mercury 2-strokes are as durable as Johnson ones.

 

[mercurymang]

Re: Mercury 2-strokes' term of life

I don't think it's really possible to answer the question hypothetically as there are so many variables involved. All that being said, somewhere out there is someone who holds the record for longest run of a Mercury outboard. That would probably be the max an outboard can be run, or close therebouts and every other motor just suffered from assorted operating environments that were less than ideal thus, decreasing there life span.

 

[Faztbullet]

Re: Mercury 2-strokes' term of life

There are plenty of 1940's & 1950's models still out there running that have never had anything but tune ups and impellers. The engine will will eventually need a overhaul as all engines do due to internal wear but most boaters are lucky to 30-60 hour a year on a motor. Heck the new motors are stated as going 300 hours without a tune-up which for some boaters could take up to 5 years to reach this mark. The life span depends on how it ran/RPM range it operated at/maintenance schedule and usage. So to answer your question a average boaters engine should last in the 2500-4500 hour range or about 20+years....commercial usage does not count as usually once started in morning they are not shut off till work is complete which can be 10hr a day and life span is considerably shorter.

 

[dandreye]

Re: Mercury 2-strokes' term of life

Well if it really costs less to maintain/repair even so old models when required rather than swap them for newer ones then it looks like my 2001-made 90 ELPTO has all chances to become my only OB unless I ever wish to switch to something else for some other reasons. Hopefully 2-stroke OB oil will still be around )

 

[Faztbullet]

Re: Mercury 2-strokes' term of life

The only problems that I see on that engine base(70/75/80/90) is reed gasket failures/lower unit gears and carb problems from improper fuel/storage.

 

[dandreye]

Re: Mercury 2-strokes' term of life

Faztbullet:

Could you please expand a bit more on that, particularly wrt storage? If winter storage is implied I don't recall any other requirements apart from winterizing it and storing it in upright position throughout the winter... During the summer everyone keeps their OB tilted up and so do I - does it cause any problems for these particular engines?

 

[Faztbullet]

Re: Mercury 2-strokes' term of life

What I see is untreated fuel(forgetfulness/uninformed)damage. A lot of the skiers and tooners with this engine run cheapest fuel they can find during operation do to fuel consumption then forget and let it set in lines. I see swollen inlet needles, fuel diaphragms,internal degradation of the fuel lines.

 

[dandreye]

Re: Mercury 2-strokes' term of life

Is decent quality fuel alone enough to make sure nothing like this will happen or it still requires adding products like seafoam to be 100% sure? I'm reading a lot of positive feedback about the latter. Unfortunately I've never seen it selling in my area.

 

[merc850]

Re: Mercury 2-strokes' term of life

Check this site to answer the old Merc question http://johnsoldmercurysite.com/phpBB3/viewforum.php?f=10

 

[Texasmark]

Re: Mercury 2-strokes' term of life

I just got through using up my bandwidth limit viewing You-tube video's on Mercs and Lake X testing. I remember the test they put the first "Tower of Power" through to prove it's reliability. As I recall it ran 24,000 miles non stop. Drivers and fuel were supplied by nurse boats coming along side as required.

OMC, back when the "Fat 50", first V4 they built went on an ocean voyage from the US to Great Britain to prove their reliability.

No telling.

If you think you can wear one out, with proper handling and maintenance, go for it. Lots of luck.

Mark

 

[dandreye]

Re: Mercury 2-strokes' term of life

24K miles @ 40-60mph is about 500h continuous operation, which is definitely not bad at all but in my opinion a lot more testing would be required to see what happens at multiples of 1500-2000h. The 1940's and 1950's models that are reportedly still around must have done a lot more by now. Well all these figures answer my question the way that with my current average hours per season I'll never have to change my properly handled/maintained 2-stroke (was just weighing the benefits:cost of switching to a 4-stroke).

Many thanks everyone for the replies!

 

[joed]

Re: Mercury 2-strokes' term of life

You should also consider that 2000 hours is 8 hours a day, five days week, for one year.

 

[dandreye]

Re: Mercury 2-strokes' term of life

Very true... btw that's about $160/day on fuel alone at cruise speeds for my engine )

 

[minuteman62-64]

Re: Mercury 2-strokes' term of life

Here in the San Diego area, a lot of the old, worn out OBs end up in Mexico. There, they may run (probably with the help of lots of duct tape and bailing wire) for another 10 years or so. Who knows how many hours they end up running?

I can't tell vintage at a glance, but I've seen some pretty old looking OBs (of all mfg.) in the harbor areas of Ensenada.

 

[MercGuy]

Re: Mercury 2-strokes' term of life

I can't answer your question, but I can tell you that I have a 1988 115 with 1000 hours on it.

If there is any degradation of performance of any type I cannot tell it. So far as I can tell it runs as well as the day I bought it.

I've done nothing but routine maintenance to it over the years.

 

[1960 Starflite]

Re: Mercury 2-strokes' term of life

Too many variables for anyone to answer My Starflite has a 1960, 300 Merc. Bought it from original owner. Not a speed boat by any means, but turns a lot of heads at the lake pubs.

 

[merc850]

Re: Mercury 2-strokes' term of life

Powerhead problems in the pre-70's were caused by lead in the fuel and bad oil (a lot of marinas had pre-mix at the pumps with god knows what oil).
Today's fuel is full of solvents but they don't cause the same damage to metal parts as lead; the use of synthetic oils can help make a motor last a long time [personal experience speaking].
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