Rough Idle

[odabe]

I have a 25 hp Merc that has the electronic shift, Model # OB140797 25M SST. The issue that I have with this motor is that it doesn't like to idle when first starting it . I end up having to shift it into gear as soon as it starts in order to keep it running. I follow this instructions on starting it, use the "primer / choke" 3 times then keep it at the 1/2 way point & hit the starter.
This is a "new" motor to me, so I figure I have to learn the little quirks of this engine. I'm used to the older outboards that have the pull out choke & separate throttle control. That was where I would leave the choke 1/2 way & be able to set the throttle to "fast idle" & let it warm up. With this engine I have to put it in gear ( reverse at the launch) as soon I get it started. Once I have it running & get going it performs just fine. After it gets warmed up it will idle down pretty good to a trolling speed.. If I shut it off & restart it, it'll fire right up & run well.
I have fresh gas (rec fuel) at 50:1 mix (TCW3 oil) & I just changed the plugs as well.
Any help / suggestions are appreciated.

 

[odabe]

Update on this issue. It looks like this is a 1997 model 25M, even though it has the electric start option. So I was looking at the choke /primer assembly & noticed that the "teeth or ratcheting gears" of the Fast Idle Lever assembly are not making contact with each other. I assume that they are supposed to grab & hold while the choke knob is out, thus increasing the tension on the arm that would increase the idle speed. Then they would release once the choke / primer knob is returned to the closed or off position.. Is this correct ?

 

[racerone]

I would suggest a new water pump impeller as an important thing to do.----Plus try to find an owners handbook.

 

[The Force power]

Update on this issue. It looks like this is a 1997 model 25M, even though it has the electric start option. So I was looking at the choke /primer assembly & noticed that the "teeth or ratcheting gears" of the Fast Idle Lever assembly are not making contact with each other. I assume that they are supposed to grab & hold while the choke knob is out, thus increasing the tension on the arm that would increase the idle speed. Then they would release once the choke / primer knob is returned to the closed or off position.. Is this correct ?

That is correct, there should be a thin metal rod connected to the (white) attachment

the link is not exactly for your motor( but with a little imagination) can be helpful
http://www.baads.org/wp-cms/wp-content/uploads/2013/10/Mercury_2-stroke_manual_PART1.pdf