78 Evinrude 9.9

OptsyEagle

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Sounds like it is running normal to me. The way that motor works is as the RPMs increase the amount of water pressure from the pump increases. As that happens the direction of the flow out the exhaust relief hole changes. At the beginning, one is lucky to feel a mist because the T-stat holds most of the water back but once that opens you should see flow like a stream out the back but the angle of that water will move towards and away from the midsections as the T-stat opens and closes and the RPMs increase and decrease.

Anyway if you ran it for 2 hours and the powerhead is just warm to the touch it is probably working fine. If it was not pumping water around the engine correctly your motor would be dead by now.
 

909

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That makes sense because the impeller RPM is dependent on the motor RPM. When there's more pressure, there's more water. The stream should get bigger and shoot out further back the more you open her up.

Just wanted to thank you OptsyEagle for sharing your experience and knowledge. The knowledge you're sharing will help many new users for years to come.

Here's a video going top speed:
 

909

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Where is the Motor Pivot Tension screw located?
Is it to the left, on the outside near the exhaust ?
 

hardwater fisherman

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If you are asking about steering friction it appears to be number 85 in the diagram. A screw with a spring. Most of my OMC motors it is in the center of the swivel tube and you need to get down and look for it. I do not own any 9.9 so not sure. If your asking about tilt friction it is number 32.
 

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909

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Yes that's exactly it.
Thank you HardwaterFisherman
 

909

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What is the correct procedure for setting the idle mixture.
 

OptsyEagle

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Start where you are or 1.5 turns out from lightly seated. Start motor. Warm it up. Bring it to a slow idle. Turn the knob clockwise 1/8th of a turn. Let it respond to that for 10 or 15 seconds. It may idle up it may do nothing. Turn it in another 1/8th of a turn. Let it respond. If it does idle up at any time turn the idle back down by reducing gas to the throttle. Keep doing this. Eventually you will turn in the dial and the motor will start to hiccup or stall. When that happens, turn it out (counter-clockwise) a 1/4 turn and leave it there forever. Place the knob so that this position is in the halfway mark between rich and lean and you are done.
 
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Sea Rider

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Remove thermo, bolt cap back on, with muffs start the motor and let it run for some time, poke a stiff wire up the peeing port several times in-out. If that motor has a small hose that connects to the lower powerhead remove it and poke same, probably there's a clog already there. ?

All lower water tubes have a diagonal cut, much easier to fit into the pump's upper rubber grommet. Running any motor on muffs, barrel at idle to check the temp won't say much, check it while running wot for several minutes.

Happy Boating
 

flyingscott

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Remove thermo, bolt cap back on, with muffs start the motor and let it run for some time, poke a stiff wire up the peeing port several times in-out. If that motor has a small hose that connects to the lower powerhead remove it and poke same, probably there's a clog already there. ?

All lower water tubes have a diagonal cut, much easier to fit into the pump's upper rubber grommet. Running any motor on muffs, barrel at idle to check the temp won't say much, check it while running wot for several minutes.

Happy Boating
Have you even read this post?
 
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flyingscott

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The post has many points have replied to 2 of them. If the op has not said anything, what bothers you? You should M.Y.O.B.....

Happy Boating
I am just trying to keep things professional. You know when you don't read the whole post, then ask questions that have been answered. Everything gets confused. Everything you asked him was answered in other posts. I was Just asking a Question God you are thin skinned.
 

Faztbullet

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All lower water tubes have a diagonal cut, much easier to fit into the pump's upper rubber grommet.
This is not true or correct as many are straight cut
 

themetalmaster

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From what I have learned is that the 74-76 did not have a separate pee hole, they came out on the 77 and up 9.9's but one can be added as a simple mod.
 

909

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Start where you are or 1.5 turns out from lightly seated. Start motor. Warm it up. Bring it to a slow idle. Turn the knob clockwise 1/8th of a turn. Let it respond to that for 10 or 15 seconds. It may idle up it may do nothing. Turn it in another 1/8th of a turn. Let it respond. If it does idle up at any time turn the idle back down by reducing gas to the throttle. Keep doing this. Eventually you will turn in the dial and the motor will start to hiccup or stall. When that happens, turn it out (counter-clockwise) a 1/4 turn and leave it there forever. Place the knob so that this position is in the halfway mark between rich and lean and you are done.

Excellent post. Well written and explained perfectly.

How should the idle speed adjustment knob be set in relation to the low idle mixture ?
 

OptsyEagle

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I assume you are talking about the knob on the side of the motor. That one I can't say. Mine has never worked and I have never needed it. I have a 1/2" boat plug stuck in the hole where mine was supposed to be. I assumed it was just a low idle stop to ensure you don't stall the motor when reducing throttle. I have never had that problem or needed a stop for that. Maybe others could give some insight into that one.
 

Crosbyman

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much like the 9.5hp it is just a mechanical stop has describded by optsy.

fine tune the needle ... lower the speed to just about shut-off turn the knob to stop any further travel which would stop the motor.

kill it with the stop button
 

909

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much like the 9.5hp it is just a mechanical stop has describded by optsy.

fine tune the needle ... lower the speed to just about shut-off turn the knob to stop any further travel which would stop the motor.

kill it with the stop button

Thanks Crosbyman . I've noticed this setting affects the travel position on the throttle handle.

I've set the idle speed adjustment to just before shut off

I've set the LEAN / RICH low jet to lean just below shut off .... from that point I added about a quarter turn counter-clockwise .... then set the knob dead center.
 

909

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Are the gains from CDI performance over points SIGNIFICANT ?
 

oldboat1

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depends on what is meant by 'significant'. Replacement parts are more expensive. Spark may be stronger, but that would depend on the conditions of the ignitions compared -- and the adjustment of the points system

hate to be a wet blanket, but that impeller pictured is a risky bet -- cracking is evident, and you don't want to block off water passages with bits of an impeller. The round knob should control the travel of the throttle handle/grip if it's intact and working. It's easy to observe the mechanism with the hood off.

Other than doubts I have about the impeller, it sounds like you have it ready to go.
 

909

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depends on what is meant by 'significant'.

Performance differences

20210805-151245.jpg


Brand new
 
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