Rated RPM for Merc 650?

[JollyBFD]

Hi, I am getting ready to take my new (to me) boat out for the first time this weekend, and want to doublecheck the engine settings. Does anyone know what the rated WOT RPMs is for a 1975 Mercury 650 65hp 3cyl outboard? Also, what is the idle speed and no load max speed supposed to be? Is it safe or beneficial to check no-load max speed on the trailer with those water "earmuffs" providing cooling? I think I read somewhere previously that you aren't supposed to go above idle out of the water. If so, what's the best way to go about adjusting WOT settings on the carbs? Thanks in advance for helping a newbie.

 

[andy6374]

Re: Rated RPM for Merc 650?

As a general rule, you should never rev above 1000 RPM's with the muffs.<br /><br />-andy

 

[JollyBFD]

Re: Rated RPM for Merc 650?

So pretty much the only way to do anything above idle with the engine (decarbing, etc) is to have it out on the lake, or maybe dip it in a big tub instead of the muffs?

 

[pinkfloyd]

Re: Rated RPM for Merc 650?

Yep.

 

[pinkfloyd]

Re: Rated RPM for Merc 650?

I dont think you have a WOT adjustment, Just idle speed air screw.