Johnson 40 lower unit seam leaks water when flushing

Rowan

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Jul 13, 2008
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When I flushed the engine after using it the other day, I noticed water was coming out of the seam where the lower unit meets the mid-section. The water comes out of the hole in the front part of the seam (which may be normal and I just hadn't noticed it before) AND it squirts out of the sides of the seam but only on the front third of the seam...any ideas? Thanks.
 

Rowan

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Re: Johnson 40 lower unit seam leaks water when flushing

I forgot to mention...this is on a 1987 (or so) Johnson 40 hp.
 

tashasdaddy

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Re: Johnson 40 lower unit seam leaks water when flushing

normal on muffs.
 

Rowan

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Re: Johnson 40 lower unit seam leaks water when flushing

Thanks tashasdaddy and go Gators!

I must have flushed this and other outboards a thousand times and just never noticed water coming from the front part of the seam...always focused on water coming out of the 'pisser'. Anyway, thanks again.
 

Tacklewasher

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Re: Johnson 40 lower unit seam leaks water when flushing

What Tashdaddy said.

Mine does exactly the same.
 

F_R

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Re: Johnson 40 lower unit seam leaks water when flushing

The hole in front is a drain hole to drain the water out when you shut it off...also drains all the rest of the time also.

As for the seam, it is supposed to be sealed with some goop whenever the gearcase is removed and reinstalled. But that is only because people get panicky when they see it leaking. Anything that comes out there was destined to go out with the exhaust through the propeller hub anyway. No problem, so don't worry.

EDIT: I just looked at the video. You do have an abnormal amount of water spraying out there. Can we assume the bolts are tight? Otherwise, continue to don't worry.
 
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Rowan

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Jul 13, 2008
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Re: Johnson 40 lower unit seam leaks water when flushing

Thanks for looking at the video...I would assume the bolts are tight, but I have no experience removing or reinstalling the lower unit so I can't confirm this. This engine has been worked hard commercially and has been solid, but it has been run aground (on soft pluff mud) 100 or more times over the years and this excess water is new...I'm thinking it finally hit bottom once too many times, but it doesn't seem to be overheating or acting funny in any other way.

Should I consider replacing the gasket (if there is one)? or can I continue to run it and watch for overheating? Or what else should I be afraid of/watch for? Thanks again!
 
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