2001 Yamaha 2.6L OX 66 Saltwater II cooling question

Sky911king

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Apr 22, 2016
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I have a "new to me" Yamaha that seems to run just great, but there is a water hose coming from the upper engine cowling running outside the upper unit that has lots of water coming out of it, warm water. It is not the cooling water discharge from the upper cowling indicating water pump operation. It appears the lower end of the hose has the remains of a plastic nipple in it. What is this and where should it be attached? Does it pose an engine hazard while it is loose? How do I fix it?
 

tommarvin

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Nov 22, 2015
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I think it's where you rinse/back flush your motor when it's in the water and you can't flush the motors LU with muffs.
You need a new part for this, a hose is supposed to screw into into it, warm water should never come out of this.
Never run your motor with the hose connected to this, it's only a back rinse,
Only run your motor on the muffs where water goes in both sides of the lower unit.
 

Sky911king

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Apr 22, 2016
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Understand about the intake and the flush using a hose bibb and muffs. Does the hose bibb on the lower unit go to the hose shown above? If so, where does it connect? Is there a check valve that prevents the cooling water in the engine from back flowing out the hose bibb connector?

I've ordered the shop manual but it won't be here for a few days. Thanks for your input.
 

99yam40

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I have never seen a hose like that on an outboard.
you will have to trace it back to see where it comes from.

but who knows what someone was trying to do with it
 

Sky911king

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Apr 22, 2016
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Thanks for your insight. I will pull the boat out of the water and trace it. Used equipment is sometimes a mystery!

Kindest Regards.
 

tommarvin

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Nov 22, 2015
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I wouldn't use the boat until you figure out the mystery hose.
It could be an extension hose for the back rinse?
The factory service manual will explain everything perfectly.
 

99yam40

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speedo hose should only have water flow if moving forward in the water.
I believe he is saying it comes out when motor is running

Water pressure gauge added at one time maybe
 

flyingscott

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According to the OP the boat is in the water and the hose looks like it is routed from the lower unit, Maybe but up a better pic. Gonna need more info does it do it when the motor is moving or standing still. Where does the hose originate from as Yamahas came with factory installed speedo hoses.
 
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Sky911king

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Apr 22, 2016
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Water flows in Neutral or in gear and pressure varies with RPMs...so guessing from the lower unit water pump. Definitely has a broken-off nipple in the broken end of the hose. Don't see any opening into engine cowling that this hose might have come from. Still awaiting shop manual.

Thanks for all your input.
 

99yam40

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take cowling off and look at the motor for leaks and see where the other end of hose goes to
 
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