Mercruiser 350 MAG MPI Leaking Water

[aboston7]

Hello,

I have water leaking on my Mercruiser 350 MAG MPI (2008). It's leaking onto spark plugs and down on the starboard side only. I checked the manifold, riser and extension and they all look good. Any suggestions? Could it be any sort of drain plugs installed that high (the level of spark plugs approx). Any assistance would be appreciated! Thank you! P.S. I've attached two videos showing the leakage.

 

[Bt Doctur]

looks like a incorrect witerization and a cracked drain fitting

 

[aboston7]

Thank you. Actually, I'm in Florida and never have to winterize. It seems to come from the left side only (starboard side). I've checked the manifold drain fitting but it's not cracked.

 

[aboston7]

Found the root cause. It was a quick drain fitting (made of plastic) that broke and a hose fell off (cheaply made). Just installed a new drain plug and all is good now.

 

[alldodge]

I'm in Florida and never have to winterize.

There is a bunch of folks in Texas that said the same thing

Glad you found the problem, and it wasn't any worst

 

[aboston7]

Actually. Just realized the issue still exists. There is another BIG leak. Attaching a new video. Does anyone know what it is? It's coming from the port side of the motor (from under the motor).

 

[JASinIL2006]

That looks to be near where the freshwater line from the transom is attached to the power steering fluid cooler. The cooler is a fitting that has large hoses (attached with hose clamps) on front and back. It's mounted fairly low on the engine but you should be able to trace a large hose coming from the back of the transom to the cooler.

I'm not 100% sure that's the source of the water, but it's in the right spot, and it would be a good place to start.

 

[aboston7]

Thank you for that! You are right. The space is so cramped. I might need to take off the manifold to reach it. Will assess it tomorrow when I'm at the boat.

 

[JASinIL2006]

My boat doesn't have much more (if any) room than that, and I can reach down and get my hand on the cooler. Removing the hoses is a bit more difficult, but still possible without dismantling anything. You ought to be able to get your hand on the hose coming from the transom and trace it it. You could then at least feel if the water is gushing out of the cooler or connections to it.

 

[aboston7]

That sounds relieving to me! I tried to get my local mechanic do it for me, but he's busy with exiting work for at least 3 months (which made me upset, as much as I love boating).