Oil in exhaust water - where is the leak?
 

Took the boat out Sunday and noticed I'm getting a fine mist of oil in the water exiting the stbd motor. I can see a ring of oil sheen in the water around where the exhaust water lands, but it don't look/feel oily if you put your hand in the exhaust stream, so it's pretty little at present.

I'm guessing it is a leaking oil cooler, but the question is how to tell which one. There are 3 coolers on that motor: power steering, trans, and motor. None show any water in the oil (not surprizing) and none show a low oil level as the leak is obviously very small.

Is there a dye I can put in the systems one at a time to see which cooler is leaking? Murphy's law would say it is the engine oil cooler as that is the hardest one to get at (bellhousing coolers with engine oil on the "inside"), but it is also the newest having been replaced when the engines were rebuilt a couple of years ago.

How to I test/locate the leak so I don't have to replace all 3 coolers?

Thanks - Greg

Are you sure it's not fuel?

G

Don't think it is fuel as motor runs fine and no smoke, but no I can't say I'd know how to tell fuel from oil.

-Greg

Take a spark plug reading after idling a while, see how rich it is and also if any are showing oil. If the coolers where leaking I'd think you would be developing a milkshake in that engine.

BT :cool:

bet its fuel.....

Agree mine does the same thing on the rich (warm Up) engine.

Are you getting water in your oil ? If your oil cooler is leaking I would expect to see some water in the oil. My guess is it is fuel. I do not know what motors you have, but most marine motors run rich and at idle there is a real possibilty of un-burnt fuel existing the exhaust.

I'm surprised that the EPA hasn't come and arrested me yet

I pollute my canal everytime I start my up my Tiger.

I've had blowers on my last couple of boats, so I'm used to dumping raw fuel at an Idle.

If you had oil in your exhaust, you probably would also have it in your crankcase.

I did some more checking last night and am guessing it is the PS cooler, as the level is down in it. There is no visible water in the fluid though (nor is there any in the engine or trans, but they both are full).

I'll check the power valve in that motor, as that would be the only thing that I can think of that would cause it to start running rich enough to have unburnt fuel (since it has not done this before and the other motor does not show the same problem, and both are timed and jetted the same).

There is no "smell" in the oil/water from the exhaust, wouldn't gas be detectable?

The oil/gas/??? is there at idle even after the motors have been out running for a hour, so I don't think it is just rich warm-up, the carbs also have no chokes (850 DP's).

-Greg

"The oil/gas/??? is there at idle even after the motors have been out running for a hour, so I don't think it is just rich warm-up, the carbs also have no chokes (850 DP's)."

O.K. guess I was wrong :D
Just keep a bottle of Dawn dripping soap behind you:p


In case you don't know what the H(&)ll I'm talking about Dawn dish soap makes an oil slick go away like right NOW:D Never leave the dock without it.