BoatBanter.com - View Single Post - Yamaha F150 break-in

HK

wrote:
On Fri, 13 Mar 2009 02:10:51 -0400, Wayne.B
wrote:

I really think WOT takes time off the life of an engine, particularly
a 4 stroke but that may just be me..
Automotive 4 strokes run at WOT for any length of time have very short
lives. I've been told by a number of people who should know that
3400 to 3600 should be about the max for normal operation, maybe 4000
for outboards.

4 strokes have come a long way in the last 20 years, mostly because of
the Japs. My Honda Prelude redlines at 7500 RPM and the cam timing
doesn't even advance until you get to 5000 (VTEC). I don't hear that
much either.
I guess I am still just old school ... but I do get a lot of hours out
of my engines.

My Yamaha F150 seems happiest cruising at 4000-4500 rpms. Redlined at
6000 RPM. I've run the engine up to 6000 rpm a few times, but not more
than a few times.