Fast Idle 1998 120HP Force

[whblaylock]

My mtr runs great and when cold started idles properly but after running for awhile and then shifted into neutral the idle is fast and vascilates from normal to high randomly. If I turn off and restart it idles okay. It just started doing this suddenly last Monday and when I ran it today it did the same thing. Any ideas as to what might be causing this?<br /><br />Thanks, WH

 

[peacekeeper6]

Re: Fast Idle 1998 120HP Force

mine does this, after it runs high and u shut it off and restart it does it "jump" sometimes? like almost like a backfuire? i havnt found the cause yet but i know it hasnt hurt mine yet.

 

[whblaylock]

Re: Fast Idle 1998 120HP Force

Yes it does. It runs smooth as silk then idles high, has a hard jump or miss, idles down then high etc... but when it idles like it is suppose to it is quite and smooth. When I run it past idle up to wot it is smooth. throttle back to idle and it starts to race some, jumps or misses idles down, then races.

 

[ljshein]

Re: Fast Idle 1998 120HP Force

My 84 force 125 does something similar. The idle seems inconsistent. I've rebuilt the carbs but I didn't do a good job of syncing the carbs. I'm blaming it on that until I take the time to fix it

 

[imported_bjs]

Re: Fast Idle 1998 120HP Force

adj.idle mixture screws.ithink you do top carb first.they are very sensitive.took me about 1 hr to get them right.adj.screws then take out and run boat hard then see how she idles.mine does the same thing from tome to time.good luck i have 1998 120 force.

 

[peacekeeper6]

Re: Fast Idle 1998 120HP Force

i will try that

 

[whblaylock]

Re: Fast Idle 1998 120HP Force

Thanks Brad for the suggestion but I will wait til I get a manual before I started turning screws. wh