Water leak from lower stern drive

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,745
Hello. When running on muffs I've got a water leak from the small hole just above the bullet on the front of the drive on my 74 Mercruiser.

I know that if gear lube was coming out of that hole it would mean I need a shift shaft seal.

What does it mean when water is coming out?
 

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ryanr623

Chief Petty Officer
Joined
Jul 11, 2008
Messages
489
Re: Water leak from lower stern drive

Hello. When running on muffs I've got a water leak from the small hole just above the bullet on the front of the drive on my 74 Mercruiser.

I know that if gear lube was coming out of that hole it would mean I need a shift shaft seal.

What does it mean when water is coming out?

That its doing its job. Its made to drain water out of the prop shaft cavity so that during winter it doesn't freeze, expand and crack the lower unit.
 

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,745
Re: Water leak from lower stern drive

Funny, it's never done it before.

I didn't think it's normal.

Pulled it apart and water tube is melted and impeller is shot.

Would shift shaft seals be shot as well?
 

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,745
Re: Water leak from lower stern drive

Apparently when on muffs I either didn't have enough water flow or the muffs weren't on quite right.

I melted the water tube and damaged the impeller. Engine didn't get too hot.
Will check flapper.

If it got hot enough to melt the water tube could it damage the shift shaft seals as well?
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
Re: Water leak from lower stern drive

Maybe, but don't just change them, I cooked my pump last spring and the shift shaft seal did not require replacement. Although I did end up changing my exhuast flappers.
 

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,745
Re: Water leak from lower stern drive

I'm going to give this a bump.

What would cause water to be coming out that weep hole?

thanks
 
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