Blew 1" Hole in Exhaust Manifold -- HELP

[DUG422]

My engine blew a one inch hole in the exhaust manifold.

There is no water coming out my tell tale hole, which probably caused the problem. I'm assuming it overheated obviously. The engine wouldn't start the other day. I found water on cylinder three and four spark plug. I wipe them down and put them back in, and the motor started right up. I can idle it up no problem, and put it in gear and rev it up and down. But still no water coming out my telltale hole.

Is it just because there's a hole in my manifold that water is getting into the cylinders? Or my looking at a bigger problem?

I do not believe the temperature sensor light came on or buzz, But I was going WOT when it blew.

I was definitely due for a new impeller. Was out fishing for three days with no problems, except on the last run in when it blew. Don't know if there was a water ever coming out tell tail whole as I didn't check. Dumb move for me, first time the boat was in the water this year.

Any thoughts or help would be appreciated. I plan on replacing the manifold cover, The temperature sensor, and impeller. What do you think my chances are that I didn't ruin anything else?

Thanks for your help in advance.

[briscoe]

Whew scary

Well, a bug could be in the little pee hole plug. Pull it off and check.
What does the oil look like. If it's not miky maybe the heads arw okay. I never heard of this before.
Good luck on your findings.

[Solarman]

I'm guessing your water pump didn't put out enough water to cool your motor which caused the hole in the exhaust manifold. If you didn't have an overheat signal then your sensor(s) may also be bad, and your tell-tale was trying to tell you your water pump was bad.

Good luck.

[DUG422]

More info

I disconnected the water line from the bottom of the exhaust manifold that goes to the telltale hole and blew through it no problem with air.

There is no water in the oil. Good sign I hope.

During the last trip"we got stuck in abay with about 1 foot of water that was pure silty mud. I trimmed it up all the way but I'm sure I sucked in some mud. Maybe some of the larger lines are clogged? I don't know.

Does the exhaust manifold have water running through it when the engine is running? When I run the engine the hole in the exhaust manifold spits out a little bit of water, With the muffs on.

But like I say it runs fine.

[Solarman]

If your water pump were good, you might have much more water going through the exhaust?

Yes, you might have pulled some mud into the pump when in the shallow water, but you may also have run the motor too high, out of the water, and burned up your impeller. You won't know till you replace the impeller (if fragmented, it ran dry, and could also have sent pieces upwards, blocking what water it could still be trying to push through.

But, one thing is certain, the more you try to run it like it is, the more damages you will have to repair.

Good luck.

[DUG422]

Took the exhaust manifold off today. The hole in the manifold is directly across from the cylinder 3 port.

Compression tests were

Cylinder 1 - 195
Cylinder 2 - 195
Cylinder 3 - 160
Cylinder 4 - 195

Anymore ideas?

Thanks