Help With 1991 9.9 Throttle End Idle Speed Knob

smeltjr

Seaman Apprentice
Joined
Jan 13, 2004
Messages
35
OK. I want to wind this project down and return this motor. Hard starting and the culprit was apparently the warped plastic cover. I have muffs on and can get the idle stable at 750. I played with the throttle end idle speed adjustment and it does nothing. I cannot see what the linkage does and what it adjusts to tweak the idle.

Motor belongs to dad and uncle and otherwise seems to start on a couple pulls now but I wanted to get it just right when I get on the water. Can anyone direct me on this or a pix on the ramblings or elsewhere where and how this is connected? I believe that the ramblings note on the 1991 and 1992 motors that he would be able to update when he got around to it. That is not a jab as the site is a true Picasso. Any direction appreciated.

btw - in my hunt for parts, one mechanic commented that sometimes the warped plastic covers can be "saved" and the trick is to lay them flat on a flat piece of glass or mirror for a while on a sunny day. Says you can sometimes get them flat again but no hair dryers or heat guns as they are quite easy to ruin. Tryat your own risk and may be urban legend but at $100 bucks a pop may be worth a try for someone.
 

Whoopbass

Senior Chief Petty Officer
Joined
Jun 29, 2006
Messages
653
Re: Help With 1991 9.9 Throttle End Idle Speed Knob

Are you referring to the knob at the end of the throttle handle? If so I believe that's for locking the twist throttle during trolling so the throttle doesn't idle back down to a slower speed.
How did the warped plastic cover make it hard to start? Seems hard to believe that would cause a problem.
 

the machinist

Senior Chief Petty Officer
Joined
May 7, 2002
Messages
711
Re: Help With 1991 9.9 Throttle End Idle Speed Knob

Sorry for me overlooking the update on those low speed adjustments of these late year motors on my ramblings articles. Because of this post, I have now added that proceedure to the articles. It is a hard to spell out without a a lot of detail that could be misunderstood, as this is rather tricky.

The warped/cracked plastic top could allow an air leakage into the fuel passageways creating a lean situation.

Hope this helps.
 
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smeltjr

Seaman Apprentice
Joined
Jan 13, 2004
Messages
35
Re: Help With 1991 9.9 Throttle End Idle Speed Knob

Thanks Leeroy. Yes I posted a pix somewhere and believe it had a massive intake leak at the back corner where it has no sixth screw. Lemme look at the ramblings again and thanks for all you do.
 
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