Coolant in motor oil !???

[wheatie]

I had a post weeks back about an overheated 4.3 V-6 merc. Thought I had the problem licked with 2 new riser gaskets. Ran it a bit last Fri. and was going to change plugs and recheck the oil 'cause I was still getting moisture in the breather tubs. I was able to drain off some more coolant out of the oil! The compression appeared fine. I have not rechecked yet 'cause I didn't want to draw coolant back into the oil system. QUESTION !!! What is the most and or other likley reasons coolant is getting into the oil pan???

[BM-FISHER]

head gasket! :depressed:

[1pump]

Cracked head or block. :depressed:

[WaterDog]

Yup, head gasket or cracked block. :depressed:

Sounds like some boat bucks too me.

B.O.A.T. Break Out Another Thousand

[Gundog]

Add intake manifold gasket or cracked intake manifold to the list, also some engines have the water pump housing and timing gear housing as one in the same they share a small thin piece of aluminum and it can break down and water will be pumped right in the crankcase. All of the above items already mentioned also.
Mike

[wheatie]

Marine shop is leaning toward exhaust manifold since I visually saw coolant in the exhaust chamber when I replaced the riser gasket. I will pull ex. off this weekend. All 3 spark plugs on the port side had evidence of antifreeze contamination. The tech is thinking upon shutdown, coolant was backflowing into the cylinders. One chamber was bound to have a valve open. Would explain hard restarts on the river. Hope he is right, just the ex. man., and I don't have to go any deeper. Found ceramic coated ones for $225.00 delivered.

[Green Machine]

Good luck and we'll hope it's just the manifold. Bummer when the fishing is starting to pick up.

Green Machine

[wheatie]

GOOD NEWS, considering the other possabilities. I just got the manifold off and pluged up the outlet and put the garden hose to the inlet and could hear air then a hissing then water appearing in the exhaust chamber. I thinks I will replace it with a ceramic coated one from Performance Product Technologies for $199 +shipping. I know I should replace both but somtimes if it ain't broke, don't fix it is much easier and cheaper!