Safe RPM for Merc 420hp
#1
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Safe RPM for Merc 420hp
I have a merc 420 hp with 110 hours on it. Tonight I did a 20 mile (each way) cruise. On the way there I ran 3200-3500rpm. One the way home I ran 4000-4200rpm. The boat really comes alive at 4000rpm. Is it safe to run it that long at that rpm?
#3
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Water got up to 160. I don't have an oil temp guage. It has a cooler on the Side of the motor that's about the length of the block, 1/3 power steering, 2/3 oil cooler. I probably should get an oil temp guage.