high idle? what's the first thing to look at

[bfan781]

1998 mariner 115hp ouboard. idle highs in and out of the water. Whats the first thing i should do?

 

[nicknight]

Re: high idle? what's the first thing to look at

throttle.

 

[bfan781]

Re: high idle? what's the first thing to look at

like check the throttle bars and make adjustments per the manual? Little confused?

 

[Sunfish12]

Re: high idle? what's the first thing to look at

What rpm's is it idling at and is this new too the engine?

 

[reddogg]

Re: high idle? what's the first thing to look at

look at the connections at the engine and check adjustment, also look at the idle set screw and check adjustment. Could also have to do with fuel/air mix ratio, is it choked?

red

 

[bfan781]

Re: high idle? what's the first thing to look at

In neutral its about 1700, in gear it drops to 1000. (per gauge). I know that too high and don't want to cause more damage. I did rebuilt carbs because there was water and "junk" in them. Can't remember how it ran before because it was running lousy because of that issue.

Should I do a lync and sync? Do I need any special ools for that. I have a lot of tools and the original manual. Just need a little guidence.

 

[nicknight]

Re: high idle? what's the first thing to look at

like check the throttle bars and make adjustments per the manual? Little confused?

well you have the manual....that is 1/2 the battle. There should be a throttle adjustment procedure in it (and a carb/idle adjustment proceedure).

The other next thing is that carb you rebuilt......last time I adjusted a carb was 20+ years ago. You are right to suspect a bad mixture.

From my dirtbike days I remember disconnecting the throttle cable and making sure that throttle off is actually throttle off.

sorry I cannot be of more help.

 

[bfan781]

Re: high idle? what's the first thing to look at

I did the lync and sync and I am at the point of checking the timing. I have original manual but not 100% sure of how to check the timing. Do you crank it over turning the key? Any advice or extra knowledge you share would be great.

 

[Coloradolakeboy]

Re: high idle? what's the first thing to look at

Has it been set that way? If a motor won't idle at low rpm it could be air in the fuel.

 

[bfan781]

Re: high idle? what's the first thing to look at

Well I went through the lync and sync in the manual and lowered the idle screw to drop the rpms to 650-700. Now it says to do the timing adjustments and then fine tune it when its in the water. Curious about how to "correctly" do the timing if I even need too.

How to do check for air in the fuel?

 

[Coloradolakeboy]

Re: high idle? what's the first thing to look at

Here is the link to test for air in the fuel and test the fuel pump.
http://forums.iboats.com/showthread.php?t=283363