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snapoffmode
08-02-2005, 01:50 PM
Hey Guys,

I was just wondering what would be considered "a lot" of hours on an outboard motor. You know how there's pretty much a standard for the usage total on vehicles like mileage. Is there some kind of standard for outboard motors?

Thanks

Ta

drstressor
08-02-2005, 01:56 PM
In salt water, we would trade in or rebuild bigger 2-stroke outboards after 500 hr. Not many get past 1000 hr. Smaller 2-stoke outboards that are not required to push heavy loads hold up longer. I would worry about small engines with over 1000 hr.

4-stroke outboards hold up much longer than 2-strokes as long as they are properly maintained. I know of several Hondas with between 5,000 and 8,000 hr on them that still run OK.

My 8 hp Honda kicker has over 2700 hr logged and it still runs fine.

snapoffmode
08-02-2005, 01:59 PM
thanks doc!

metalmouth
08-02-2005, 02:19 PM
Doc, how many hours between service?

drstressor
08-02-2005, 02:41 PM
I use Mobil 1 10W-30 in both my 8 hp and 90 hp Hondas. I change the oil twice per year on the 8 hp and every 50-75 hr on the main engine. My main engine gets very little use and has just under 300 hr on it. That works out to every 18 months or so. I have done oil analysis to verify that the oil is still in good shape and that wear rates are low with the long change intervals.

I've had problems with water accumulating in the oil in the little engine twice since 1998. This was caused by the thermostat failing. After one failure, the oil analysis came back indicating huge amount of copper and the suggestion that bearing wear was excessive. This was not surprising since the oil looked like milk. I did a short cycle (1 trip) with conventional oil to flush things out before going back to M1. The darn thing still runs fine.

metalmouth
08-02-2005, 02:53 PM
Thank you ;D

Oxbow
08-02-2005, 02:55 PM
Doc, is the thermostat an easy change or a dealer job? I worked on aircraft and hot rods as a reference point.

Thanks!

drstressor
08-02-2005, 04:09 PM
It's very easy on small engines. You just remove some wiring and hose harnesses to make some room and then take off the exhaust manifold. Be sure to replace both the inner and outer gaskets when you do the thermostat. No need to use any type of sealing compound. Just don't over torque the bolts when you put everything back together.

I read where Honda now recommends replacing the thermostat every 2 years. That would have worked for me. I haven't had to replace the thermostat on the 90 hp as yet so I don't know how big of a job it would be.

Oxbow
08-02-2005, 04:16 PM
I have 1999 model 15 hp kicker, sounds like I should be thinking about changing out that thermostat. Thanks for the update!