200 merc optimax high idle

bigojaydog

Recruit
Joined
Jun 4, 2003
Messages
4
just got a new boat with a 2003 200hp mercury optimax and it seems like it runs to high at idle when u first start the motor it runs at or around 600 but then all of a sudden it will jump to 1000 1100rpms and stay like that even after its warmed up but once u put it in gear it runs low again the motor only has 4 hours on it is this normal or is it because its in the break in period still.
 

graddy

Petty Officer 2nd Class
Joined
Apr 3, 2003
Messages
150
Re: 200 merc optimax high idle

That is not normal. Take back to dealer and have them check it out.I would not try to shift this engine at a high idle it could cause lower unit damage.
 

graddy

Petty Officer 2nd Class
Joined
Apr 3, 2003
Messages
150
Re: 200 merc optimax high idle

I work on alot of Optimax engines and this is a simple problem to fix. Do not attemp to fix youeself. Take it to a dealer that knows how to work on Optimaxs. Call Mercury if dealer cannot fix it.
 

bigojaydog

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Jun 4, 2003
Messages
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Re: 200 merc optimax high idle

what does it involve to do as long as its somethin not electronic i could do it myself thanks for the info.
 

graddy

Petty Officer 2nd Class
Joined
Apr 3, 2003
Messages
150
Re: 200 merc optimax high idle

You would be better off takeing it to a dealer. You have a factory warranty.
 

graddy

Petty Officer 2nd Class
Joined
Apr 3, 2003
Messages
150
Re: 200 merc optimax high idle

Does your boat have Smart Craft gauges?
 

bigojaydog

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Jun 4, 2003
Messages
4
Re: 200 merc optimax high idle

yea it has smartcraft. the reason why i want to know if its somethin simple is that my dealer is a hour and a half drive away so thats why i would like to do it myself if its not complicated.
 

graddy

Petty Officer 2nd Class
Joined
Apr 3, 2003
Messages
150
Re: 200 merc optimax high idle

If you are able to get to the fuel tank sending unit. That if the float system that sends info to the engines ECM for the level of the fuel in the tank. There is a two wires going to that sending unit, black/orange and a pink/black. Disconnect the black/orange and tape off with eletrical tape.
 

bigojaydog

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Jun 4, 2003
Messages
4
Re: 200 merc optimax high idle

Thats it and it will be fixed how does that lower the idle ? have you done this?
 

graddy

Petty Officer 2nd Class
Joined
Apr 3, 2003
Messages
150
Re: 200 merc optimax high idle

That is just one the easy checks to make and the most common high idle problem. If it works, I will them explain to you why it will cause a high idle.<br /><br />FYI OPtimax should idle at 550-580 RPM's
 

woundup

Cadet
Joined
Jul 27, 2003
Messages
26
Re: 200 merc optimax high idle

My Opti just recently developed this high idle problem also. Could you explain why the sending unit wire would cause high idle. My engine is a 1999 200 not under warranty so any info would be helpful. I haven't tried your fix yet, but I'm open to ideas.
 

fireman83

Recruit
Joined
Mar 25, 2012
Messages
2
Re: 200 merc optimax high idle

I currently have the same issue. I have a 2003 murcury optimax that is high idealing.. I havent had this promble before untill i a few months ago. can you explain why the fuel ascending unit may be the problem?? I do have a smart craft system..
 

fireman83

Recruit
Joined
Mar 25, 2012
Messages
2
Re: 200 merc optimax high idle

if you are able to get to the fuel tank sending unit. That if the float system that sends info to the engines ecm for the level of the fuel in the tank. There is a two wires going to that sending unit, black/orange and a pink/black. Disconnect the black/orange and tape off with eletrical tape.

can you explain why..
 
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