2005 Yamaha 150HP water pump drive shaft leaking.

sr79

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Install new Yamaha water pump kit on my 2005 150HP. Started engine with muffs on, observed large amount of water shooting from the small drain hole on the side. Removed lower with muffs still on and noticed water bubbling up around the drive shaft which explained water at the drain hole. Question: what should I do the fix this problem or is this something normal? Thanks for looking....
 

crazy charlie

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A pic would be helpful.Are you talking about the top of the water pump housing where the drive shaft goes thru?
 

sr79

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A pic would be helpful.Are you talking about the top of the water pump housing where the drive shaft goes thru?
Yes, the top of the water pump where the shaft goes through. All replacement parts are OEM, it just seems like the shaft seal should prevent any water from coming out around the shaft.
 

99yam40

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Have you ever paid attention to the way it was before you changed to water pump?

what shaft seal are you talking about?
none on the drive shaft that I know of.
 

crazy charlie

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Yes, the top of the water pump where the shaft goes through. All replacement parts are OEM, it just seems like the shaft seal should prevent any water from coming out around the shaft.
Rubber grommet must be installed into the top of the water pump housing at the opening for the driveshaft.I mistakenly left mine off last month while doing a water pump service.Sounds exactly like what happened to me.As 99yam40 mentioned ,always take note of how things were before the change or save old parts during a changeout as a reference. Charlie
 

boscoe99

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How were you able to see the water pump with the lower unit installed?
 

racerone

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Post #1 says he removed lower unit again.====And yes, water comes out of drain holes when running on muffs.
 

sr79

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Have you ever paid attention to the way it was before you changed to water pump?

what shaft seal are you talking about?
none on the drive shaft that I know of.
That's right there is no seal directly on the shaft. the only seal is the O ring between the SS impeller housing and nylon cover. Yes, I looked closely at all the parts and even reinstall old parts and still water from the muffs goes through the pump and out around the shaft. this was done with lower unit off and with muffs attached. It looks like water is bypassing the O ring, is that possible? Thank you....
 

sr79

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How were you able to see the water pump with the lower unit installed?
Can not see water with lower unit installed. But, lots of water shooting out small drain hole so, assumed water leaking from around shaft. I don't think there should be any water coming out of drain hole when motor is running.
 

boscoe99

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Post #1 says he removed lower unit again.====And yes, water comes out of drain holes when running on muffs.
He must have been able to remove the lower unit in a nanosecond so as to see water flow from the water pump.
 

racerone

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No----He left muffs on the lower unit to find the leakage.----But I do not believe there are any issues with this simple water pump and the theory of operation !
 

99yam40

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Can not see water with lower unit installed. But, lots of water shooting out small drain hole so, assumed water leaking from around shaft. I don't think there should be any water coming out of drain hole when motor is running.
Have you ever watched your motor before while running on muffs?
seems to me they all have water coming out of lots of holes
 

sr79

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Here is water flow from the water pump in action.
Thank you for the cutaway picture which clearly shows water flow coming out from around the shaft when engine is running. I’m sorry to say that I’ve never payed any attention as to where the water comes out when running with muffs, that is, until now that I changed the water pump.
This completely address any concerns that I may have had. This may also be very informative to other boaters.
Thank you!
Dennis
 

sr79

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I’ve never payed much attention to where the water comes out when running with muffs but, I think you are right and I’m coming to the same conclusion. Thanks for your comments…
 
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