Water in valve cover going to carburetor on 3.0 L 1999 Mercruiser. Need Help!

[WSchnellenberger]

I have a 1999 Mercruiser 3.0 L Compression on all 4 cylinders is between 160- 170 lbs. water in crankcase also. Changed oil, started engine on muffs. Ran at idle for 5 minutes saw water and oil coming from tube on pvc to carb. There was enough water to kill the engine. Boat has run fine all summer then all the sudden died running at 3200 rpms.

 

[kenny nunez]

You may have a hole in the cylinder head. For this test you do not need to run the engine. Connect a garden hose to the port where the drive pump connects to the thermostat housing and remove the valve cover. Just let the water go through the engine and if you are lucky it may only be the head. If not leaking there then you will need a new marine long or short block depending on your budget.

 

[Scott Danforth]

First time running this year? If so, you have a cracked block from poor winterizing

If not, you either have a crack or the head gasket failed

 

[Bondo]

Boat has run fine all summer

Ayuh,..... Welcome Aboard,..... 'bout how long is All Summer,..??