water in oil

[Rich Novak]

1972 omc 225 sterndrive electric shift 307 cu.
Water in #2 cyl.
Both heads had cracks ,replaced with new ones.
Started up still water in oil, pulled back apart water still in #2.
Can't see any crack in cyl. Or block.
Can a faulty exhaust manifold cause water to get in the cyl.??
All the gaskets looked OK when I took it back apart.
Any help please.
Thanks, Rich

 

[Scott Danforth]

Can a faulty exhaust manifold cause water to get in the cyl.??

YES

 

[Rich Novak]

YES

How can I check the manifold.
Thanks, Rich

 

[HT32BSX115]

Can't see any crack in cyl. Or block.
Can a faulty exhaust manifold cause water to get in the cyl.??

Thanks, Rich

Yes it can, but the amount of water allowed in is minimal. It doesn't usually cause the water in the oil to be visible.....and since the amount of water is small, running the engine at normal operating temp will evaporate the water out fairly quickly.

It will however, cause a hydrolock if you shut it down and then try to start afterwards several minutes later. The water will run right into an open exhaust valve and sit right on top of the piston.

When it happened in my previous OMC 460, if I let it sit for more than about 30 min, the water would eventually leak right past the piston and the engine would crank right up. If I tried to start it within a few min of shutdown (like picking up a skiier) it would hydrolock briefly, and then start after a few trys.

Mine was leaking water right past the riser gasket. Once the engine was running any water leaking into the exhaust system went right out with the exhaust.

Until you do a cooling system pressure check, you will not know if you have a cracked block or not.


Regards,


Rick

 

[Rich Novak]

Yes it can, but the amount of water allowed in is minimal. It doesn't usually cause the water in the oil to be visible.....and since the amount of water is small, running the engine at normal operating temp will evaporate the water out fairly quickly.

It will however, cause a hydrolock if you shut it down and then try to start afterwards several minutes later. The water will run right into an open exhaust valve and sit right on top of the piston.

When it happened in my previous OMC 460, if I let it sit for more than about 30 min, the water would eventually leak right past the piston and the engine would crank right up. If I tried to start it within a few min of shutdown (like picking up a skiier) it would hydrolock briefly, and then start after a few trys.

Mine was leaking water right past the riser gasket. Once the engine was running any water leaking into the exhaust system went right out with the exhaust.

Until you do a cooling system pressure check, you will not know if you have a cracked block or not.


Regards,


Rick

How can you pressure test an open cooling system.
I think I am expecting the hydrolock .
After mine sits over a day it doesn't want to turn over a few bumps on the starter will free it up then it starts.
I get a lot of water in the cyl.
Thanks, Rich

 

[Scott Danforth]

Start with the stickies at the top of the forums

http://forums.iboats.com/forum/engi...es-outdrives/479878-adults-only-no-exceptions

you pressure test an open cooling system like you would test any cooling system. block off the inlet from the raw water pump (hose from transom), and block off the outlet to the manifolds. pressure test to 15psi

 

[HT32BSX115]

Yeah. Just treat the block, heads and intake manifold as a pressure tank with many openings.

Close off all those openings (except 1) using ordinary plumbing fittings/hose etc.

Connect a gage, valve and quick disconnect fitting. apply approx 15-20 psi and close the valve. (The gage should be on the engine side of the valve so you can observe the pressure with the valve OFF)

Note I didn't mention the exhaust manifolds and risers.........

You cannot easily close them off since they're open at one end (the exhaust end)............But you can isolate them. (you could in reality remove the risers and bolt plates to the manifolds where the risers go, but it would be hard to detect leaks since the leak might be the plates and gaskets sealing them.......AND you can also do that to them individually once completely isolated from the main cooling system)

The block/heads/intake manifold should easily hold 15 psi or so for hours...... If it doesn't, listen for the hiss!


Cheers,


Rick