150 merc carb 2006 overheating at half throttle against tide?

[john h miller]

i have 150 merc outboard 4 yrs old at idle and plainded off temp stays in middle but when fighting hard tide temp goes up over 200 to 210 water pump and thermostats pretty new thanks for any help.

 

[sschefer]

Re: 150 merc carb 2006 overheating at half throttle against tide?

i have 150 merc outboard 4 yrs old at idle and plainded off temp stays in middle but when fighting hard tide temp goes up over 200 to 210 water pump and thermostats pretty new thanks for any help.

You may need to sacrafice a little top end and prop it down a few inches in pitch. Those temps will cause scuffed pistons on a heavily loaded engine. The alternative is to use the tide charts and time your trips so it compliments you. Nothing new about that little navigation trick.