I checked one side of the exhaust manifold (took it off) and I didn't see anywhere in the gasket where water runs through it. Or oil. Did I just not see it? I know the raw water exits through the exhaust, but it enters in the manifolds themselves after the gaskets. So how exactly does a cracked manifold gasket allow water to get into the engine oil?
A head will usually crack on the piston side which will probably not result in water in the oil. Same with a head gasket. If your head cracks in the rocker side, then water can get into the oil, also if your head gasket goes between a water jacket and lifter bay, water in the oil will result. You could have a bad intake gasket, that's where I'd start. Run the engine on muffs and see if there is any white smoke. I hope it is a gasket problem and not a cracked block.
Malibu Wakesetter 23XTI Bryant 214 Limited (gone, but not forgotten)
So how exactly does a cracked manifold gasket allow water to get into the engine oil?
It's the exhaust manifold itself that cracks or rusts out internally, allowing the water jacket to leak into the exhaust runner. When you turn the engine off the manifold drains through the crack, into the exhaust port of the head, and into the cylinder bore. It usually doesn't maike it all the way to the crankcase, though.
Has the boat had the bilge fill with water? If so, it may have entered via the oil pan to timing cover gasket area.
The oil in the water thing has been a problem since my aunt gave me the boat. Oil has been changed countless times and still the milkiness returns. It was a free boat so I'm slowly trying to find the culprit but at the same time enjoying my time on the water. I bought ALL the gaskets for the entire engine last summer, I'm just not sure if I want to replace them all myself or have someone rebuild the engine for me.
I believe I had a 5.0 in a 21 ft Bayliner from 89 and I had closed cooling system on it. It continued to give me problems with overheating and finally I just removed the heat exchanger and let it just take in raw water. Cured the problem. I had by then though blown the head gasket and that does not bring water in the oil but it blows coolant or cooling water out the exhaust through the cylinders.
How fast does the oil show milkiness? Do you see it in the pan or inside the valvecovers (on the filler cap). If it is in the upper end and not that much in the pan I would not worry just run it as it was free etc. If it rapidly shows up in the pan then you may need some new parts.
Glad to hear it. In the West marine catalog, there are OMC/Cobra manifolds listed. I have never tried to order any of them. (I might look at a boat that has a Cobra drive, real soon, so I may need parts someday!)
Dude I went through this this spring . It was the exhaust manifolds. I took everything apart all looked good comression was good and found by trial and error. Water would only leak in as the boat would cool found it by doing a comression check after using and finding water leaking into a cylinder. Compression was great at the time go figure. Get good manifolds and remember...
Its better to be on the water in an old boat than on the hard wishing you had a boat
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