Mercruiser 5.0 MPI getting water in bilge, increases under way

EricP-NH

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Aug 20, 2016
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Hi,

I am getting water into the bilge and it happens more as I get under way. At idle it seems to be very little but as I increase RPMs and speed it seems to be a lot more. The bilge pump can keep up with it, but that isn't safe. Just mentioning to give an idea of volume. I am curious where I should look for this type of problem.

Thanks,
-Eric
 

alldodge

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If no water comes in when motor is OFF then start with the intake hose. Follow the hoses around, get a camera down where you can not see to look around. Is this an Alpha or Bravo?
 

alldodge

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If your speedometer is not working, or not working correctly check the tube
 

tpenfield

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Are you seeing water accumulate if the engine is running, but the boat is in neutral (i.e not moving)?

Can you see where water is leaking? As mentioned, the speedometer tube, if not connected will put a stream of water into the boat while underway. Additional possibilities are a leak in the cooling system . . . hoses loose, etc.
another possibility is the engine itself leaking.

Got an history as to when this all started, etc?
 

EricP-NH

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Aug 20, 2016
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This just started yesterday that I know of, last ride was maybe 3-4 weeks ago and I didn't notice any issues. I don't feel any loss in power. I first noticed a problem after about 15 minutes at greater than no wake speed. I noticed weight in the back and then she ran sluggish so I fired up the bilge pump. Once I ran the bilge pump and it got everything out it ran well again. While under way I can run the bilge pump and there are no performance issues. I didn't have time at the end of the day yesterday to do any triage. I am hoping to try a few things after work.

At idle or no wake speed, I don't see any real problem, there is a some water at that point for sure, but not much, it gets worse under load.

Thanks,
-Eric
 

tpenfield

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Well, you are going to have to take a more detailed look and narrow it down. If it recently started to leak, it will probably get worse.
 

Bondo

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Ayuh,.... The Only way to find a leak in a boat if to actually See, exactly where it is,...
 

Scott Danforth

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to add to that, bring a flashlight, your cellphone with its camera, a mirror on a stick. with the boat in the water, fire it up and look. just be careful of rotating belts.
 

Bondo

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Ayuh,.... It appears the single point drain system, didn't drain,....

If ya can get that plastic ball outa there, it can be epoxied,....

Personally, I'd strip the entire single point drain system, 'n put plain ole brass drain plugs in the block, 'n manifolds,....
Then when ya drain it, you can verify it's Drained,....
 

EricP-NH

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Aug 20, 2016
Messages
25
I replaced the water distribution housing and all is well.

Thanks all for your input.

-Eric
 
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