Water pump 35hp Jonson 1981

Replaced water pump(kit) reinstalled the lower unit,started motor( mouse ears) , no water at pee hole, shut it down. Pulled pump, the water pump impeller housing had slipped ( don’t know how, it has two ears that fit in two slots in the water pump housing) beyond me. Pump housing had some damage to it. Cleaned the housing up, put pump back together, made sure the ears on the impeller housing were lined up, and the water hole was also lined up. Reinstalled lower unit, tried again, same thing happened, pulled lower unit again and found the same thing, this time the water impeller housing was totaled . My question is why or how did the water pump impeller housing slip out of the holder???? Can I two part expoy the water impeller housing to the water pump housing .

Did you put some type of lube on the impeller?

Yes used grease, Was a new pump, yes it showed black marks on the impeller housing, square muffs, (trash can now)have to order new pump now .

You might want to check that the water inlet passage is not blocked with sand or such.

CedarRiverScooter said:

You might want to check that the water inlet passage is not blocked with sand or such.

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This reminds me, I need to go home and throw my muffs away.

Yep, pull the whole pump assembly out, and remove the grates from the lower unit pickup, make sure it's clear.

I grenaded the water pump in a Suzuki I was reviving once, neglected to remove a giant ant's nest that had been built behind the grates.

I’ve done it all, pulled pump, pulled water jacket, pull thermostat and changed to a new one. I made a garden hose adapter, to hook up to the water tube , with the foot off, turned on water hose, had flow every where. I’m picking up a new pump, and going to use 8400 sealant to glue the water pump impeller housing to the water pump housing , and extra sealant on the two tabes, on the water impeller housing to water pump housing, making darn sure the water slots all line up.

Riverboatboy said:

I’ve done it all, pulled pump, pulled water jacket, pull thermostat and changed to a new one. I made a garden hose adapter, to hook up to the water tube , with the foot off, turned on water hose, had flow every where. I’m picking up a new pump, and going to use 8400 sealant to glue the water pump impeller housing to the water pump housing , and extra sealant on the two tabes, on the water impeller housing to water pump housing, making darn sure the water slots all line up.

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Are you putting the impeller in the correct direction? If it's backwards, the housing could be spinning when the impeller bunches up to go the other way.

My manual says to seal between the pump plate and the lower as a suction leak is worse than a pressure leak. I maybe would surface plate the bottom of the housing but not use goop there.


I usually make a gasket using very thin gasket paper for the plate/lower interface. That also helps seal the housing/plate area.

Pappy said:

Okay....the square muffs have a history of not being able to supply water to an outboard. You did well throwing them away. That was probably the whole source of your issue.
Now....as far as the inner cup rotating I want you to go in and see if the plastic housing shows any signs of melting or getting hot.
The reason I mention this is that I sort of knew the black marks would be there if you had the square muffs. That can and will melt a housing and allow the cup to rotate because the impeller is grabbing the cup really hard with no water to lubricate it.
With a good set of muffs that fit tight there is no need to "over seal" the pump assembly. That is or was not your issue.

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Yeah, I would be worried about the sealant getting in somewhere it does not belong.

Thank for all the help, picking up new pump, while on trip. While in stall,new pump when I get back. Will let everyone know how it goes.

She’s peeing now, Wa hoe, I’m going now. New water pump kit, 5200 the impeller housing to the water pump housing, making sure to a-line the two tabs, to the two cut out in the pump housing, extra 5200 here, will never slip again. Made dang sure to put the water pump impeller in properly. All works well now, headed to the river now. Thanks for all the help