Mercury 1999 2 stroke 2 cyl 40 horse

trackerman18

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I had the problem of my motor stalling when it idled in nuetral so I removed and cleaned the carb and reinstalled it and the problem dissapeared, only to start a new problem. I adjusted the idle screw so that the motor would idle at 800 in gear with the motor in a can of water. It will idle perfect now all day long, but when I throttle it up a little and go back to nuetral it is at about 1200 rpm or higher and won't go back down until I adjust the throttle arm with my hand. Is there a proper way to do this and is there a good manual I can get for a resonable price that shows these steps. I had purchased a Seloc manual for my engine but it seems not to cover my particular modle in enough detail that I can figure this out. New to boats, any help would be appreciated, want to start fishing soon!
 

oldman570

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Re: Mercury 1999 2 stroke 2 cyl 40 horse

Is the motor a tiller or console motor? There are diffrent settings that must be done when the carbs are cleaned or rebuilt to get everything back in sync. This is probbly what is causing the trouble.
 

trackerman18

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Re: Mercury 1999 2 stroke 2 cyl 40 horse

Is the motor a tiller or console motor? There are diffrent settings that must be done when the carbs are cleaned or rebuilt to get everything back in sync. This is probbly what is causing the trouble.

It is a console motor on a bass tracker boat:)
 

trackerman18

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

I messed with the motor some more and figured out that I can take off the threaded arms that link the throttle peices together and adjust by hand and put the arms back in place to hold everything where it should be. Have'nt tried to fire it up yet and mess with though, maybee later. I just want to know if I am on the right track. Do I have to mess with timing after these adjustments or not? I read somwhere that these motors timing can't be adjusted, just checked to make sure it is right, is this right. My serial number is: OG963923 and it is a merc 40 horse, 2 cylinder, 2 stroke, single carb outboard on a tracker boat. Thanks for any help
 

oldman570

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

The threaded cables from the control at the motor can be adjusted. The linkage for the timming was set at the factory and should never need adjusting unless someone has already done so. If that is the case I would do a complete link and sync on the motor. A OME manual for the motor will be the best, and is a cheap investment when working on the motor. A web search for Boatinfo.com should get you a online manual for your motor that you can download or copy if need be. JMO
Oldman570
 

trackerman18

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

I will look into getting that manual, Thanks for the info. I think I have read enough in the past few days on these forums that I feel a lot more confident that I can adjust this without screwing it up. Thanks for the help oldman!:)
 

carholme

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trackerman18

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Thanks Gerry, thats a great link, I did already find the manual from mercury and it is on the way. Do you know if I need the service manual or just the owners manual to show me how to adjust the throttle linkages?
 

carholme

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Service manual is the best as the owners manual is just an operations and systems description.

Gerry
 

trackerman18

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

I got everything adjusted and it seems like it runs good. New sparks, clean carb, timing checked out and compression is 120 psi on both cylinders. My whole reason to start messing with the motor in the first place was that I thought it idled a little high. I got it set so that it idles at about 800 rpm in gear, according to the tach on my steering console, which is what the manual says it should be. It seems it is a little high in nuetral, 1000 to 1100 rpms. Is this normal or should that be lower? Everyones help has been very valuable, thanks.
 

carholme

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

The manual says 700-800 so if you could get it down to 700 while in Fwd, it will probably drop your Neutral idle a bit which will make shifting a bit better. When shifting, shift positively, do not try to baby it into gear.

Are you on the lake, in gear while adjusting? Do not try to set it on muffs. Good back pressure while on the lake will allow you to get the best setting.

Gerry
 

trackerman18

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Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Re: Mercury 1999 2 stroke 2 cyl 40 horse-please help!

Not on the Lake, but it is in a garbage can full of water when I was adjusting things. Since its not too far off from where I want it, I think I will do the rest of the adjustments on the lake. Thanks Gerry, you have been helpfull, Happy boating:)
 
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