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1990 9.9 Johnson

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Red77

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I'm having trouble getting water to flow I have took the whole thing apart nothing blocked, put back together and still no water, just put water pump in thought that might fix it does anyone have any idea
 
That is just barely at the pump level you should follow Racer's advice. If still no water flow you may need to dig deeper. When did you first notice the water problem, and did it ever overheat? Is the paint discolored on the exhaust cover or cylinder head? Maybe pee hole is plugged......what did the old pump impeller look like.....any damage?
 
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I bought the boat a few weeks ago it set for about 3 years I did the water pump cause the pump was stiff thought that was it but no pulled the thermostat it had busted I pulled the chunks out so I pulled the whole motor apart nothing blocked hope it is the bucket
 
Red77 said:
I bought the boat a few weeks ago it set for about 3 years I did the water pump cause the pump was stiff thought that was it but no pulled the thermostat it had busted I pulled the chunks out so I pulled the whole motor apart nothing blocked hope it is the bucket
Click to expand...

The water pump IS NOT a self priming pump, meaning....... the water pump must be submerged in order for it to function.

You obviously know where the water pump is located... the water level must be 3 or 4 inches above the top of the water pump. A regular size plastic trash can serves this purpose well.

Hopefully you haven't damaged the new impeller by running it dry. Let us know what you find.
 
I tried more water bigger trash can so went got muffs and the only way it would trickle water is to hold the muffs tight,and took it back apart blew smoke in it and all of it come out outlet tube an the bypass hole bearly any out the nipple same with water. Don't have the thermostat in it, it busted, even took thermostat cover off while it was running and it had a little steam no water, the intake has water ports right thinking they might be closed
 
Install a new thermostat. It creates back-pressure needed to have the water telltale function properly.

Clean the plastic telltale fitting with a piece of wire.

Drop the lower unit, dismantle the water pump for inspection.

Don't try to guess-work the engine... there are water passages... there are no ports or valves!
 
The reason I ask about the passages in intake is the thermostat busted in little pieces I pulled out some but not enough to rebuild the thermostat
 
I'm novice at this is the reason for all the over thinking, car I'm ok with but boat motor is new thanks for all the info
 
joereeves said:
Install a new thermostat. It creates back-pressure needed to have the water telltale function properly.

Clean the plastic telltale fitting with a piece of wire.

Drop the lower unit, dismantle the water pump for inspection.

Don't try to guess-work the engine... there are water passages... there are no ports or valves!
Click to expand...

I understand that it the thermostat builds pressure but wouldn't water still be there behind the thermostat cover without a thermostat
 
I had similar issue with my 6hp, turned out to be a grommet which sits at the top of the water intake pipe where it meets the powerhead over time these are apparently very common to perish and fold over fully or partially blocking the intake.

Good news is the part is cheap but requires removal of the powerhead to access the grommet and replace however its pretty each and there is a good video on You tube under Brandons Garage which shows you how it all comes apart.

Replaced mine and pumps perfectly now
 
+1 regarding the grommet at the top of the water tube .... A real PITA on my 6hp ... So much so I have modified the "connection" at the top of the tube. (Now uses O rings and specially made nylon spacers instead of the grommet)

The 9.9 is not exactly the same but may still suffer from the same problem.

Two ways to check ........

While the gear case assembly is off push a stout wire up the water tube. If it hits something squidgy at the top that's the grommet folded over the end of the tube ( or a piece of broken water pump vane). If it hits something hard and solid all should be OK

Connect a hose to the water tube and check that you get a good water flow out of the telltale, to the thermostat housing and through the whole cooling circuit if the thermostat housing cover is refitted


BTW See LeeRoy's ramblings for just about everything you will ever need to know about the 9.9 http://www.leeroysramblings.com/Outboard Motor Related/OMC outboard related articles.html
 
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vics said:
+1 regarding the grommet at the top of the water tube ....
The 9.9 is not exactly the same but may still suffer from the same problem.
Click to expand...
Vics, the 9.9 suffers from the exact same problem. I chased cooling issues on my 1979 Evinrude 9.9 for over a year. Water pump, thermostat, telltale, align water tube.....I did all the usual stuff. Then, JoeReeves mentioned the grommet at the base of the engine. When I tore mine apart I found the grommet was swollen and distorted to the point that the opening was barely the diameter of a pencil lead.

After replacing the grommet and cleaning passages in the exhaust bypass cover the engine has ran like a champ for 3 years now.
 
Fixed that it fell out when I got it apart even made a clip to hold It in place it's nice and tight the other tube the outlet is loose but but not falling out or swelled I didn't seal it cause it's outlet, water gets into the motor and straight out of the outlet tube
 
what do you mean you made a clip to hold it in? The only thing that should hold that tube in is the rubber grommet in the exhaust tuner.
 
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If you are saying that the water tube was so loose that it simply fell out of the top grommet when you removed the lower unit...... you'll need to remove the powerhead in order to install a new top grommet.
 
There is two little ears on the exaust tuner that I wrapped a stiff wire around would send pic but it won't let me, it was made that way
 
Flying Scott .There is two little ears on the exaust tuner that I wrapped a stiff wire around would send pic but it won't let me, it was made that way
 
Joereeves I took power head off and when I took exaust tuner off the tube fell out cause I turned it over to blow through it to see if it was stopped up
 
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