1988 mariner 115 hp help

Hey everyone new to this forum. Have a 1988 merc mariner 115hp. Ok. This engine has been giving me some issues. First off wouldnt idle in the water but on muffs idled fine. So I just adjusted the throttle links to the top carb so the carb plates would be cracked alittle open causing it to idle around 1700 out of water but when in water was around 900 to 1000. I know not the proper way to adjust idle but had to make work with what I had and the situation. Put about five or.six hours running no problem throught all rpm range no problems. Was going to look into adjusting timing and fixing the idle properly, but in water on that day while the engine was cold it wouldnt even reach over 3000 rpm, no power or torque to.plane. just plowed water. After about five minutes u could hear and feel possibly rest of the cylinders starting to fire surge with power for a split second off and on. Then bam all power again running all day long no problem. This has occurred twice now. Hoping someone has had similar issue. Have not checked anything yet. But while it was running like crap I would squeeze primer bulb no change bulb stays firm. Also pushed choked to see if it wakes up. But it just chked out and died. Someone please help. Not to familiar with the engine. But do.have experience in automotive field knowing how to use ohm/vol reader and what not.and I dont have a manual for this engine which I should I know and probably wouldnt be here.

maybe 1 carb had needle/seat problem?is this a 6 or 4 cyl?

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Originally Posted by mn808gade

maybe 1 carb had needle/seat problem?is this a 6 or 4 cyl?

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Its the inline six engine. I have taken apart carbs cleaned, replaced one float cause was cracked and carb was spewing gas.
and have the screws adjusted out 1 3/4 turns approximately.

The carb butterflies are to remain closed until well past the mid range. If you set the carbs cracked to keep your idle up it will be leaned out when it tries to accelerate.

Those engines use advance to get the ball rolling well before the carbs even crack open. The carbs open up late in the game.

Figure out proper set up and go from there. It will never run right with the carbs cracked open.

You may have other problems as well, but you must first get the lync and sync proper.

C

I'm probably going to have to get a manual for this. I'm not too familiar with the link and sync. I have the concept of timing I'm pretty sure. disconnecting throttle cable, adjusting to 20 to 21 degrees at closed throttle crank speed. is there an advanced module I would have to disconnect? wouldnt mind having a step by step on how to do it haha, but I'm sure there's a lot of information too much to type. not trying to be an inconvenience here.

All my inlines I currently run are distributor models. The ADI versions I am not up on the particulars. But the carbs work the same. They come on late after advance is thrown in.

My manual does not cover the ADI versions. Someone here can get you the exact specs for the lync/sync.

C

Alrighty. Thank you