I'm losing P/S fluid somewhere. Nothing obvious , but last Sunday I emptied my p/s pump reservoir in 17 miles . Getting some milky exhaust water at times. Could my p/s cooler be leaking into my water system and discharging thru the exhaust? Never seen this before...anybody else? Looking for ideas before I try to remove the cooler for testing. I've got twins and you can guess where the cooler is

I've heard of this happening before. Sounds like a good possibility. That is a large leak! I would think the source would be more obvious. Anything on the transom near the rams/lines?

Nope , but your right it is a major leak

Ttt

I would try dissconnecting the lines at the P/S pump and pressure testing the cooler remotely that way you dont have to break your back removing it if nothing is wrong with it.

Mopower,
Had the exact situation as yours. Even though I disconnected the hoses to the cooler when I winterized the engine (entrance & exit), apparently there was enough water left in the cooler to freeze. It put a hairline fracture in the end cap of the cooler where it meets the body. The internals must have been compromised also as the fluid (while under pressure) was forced into the coolant stream and exited the exhaust. If I reached under the exhaust manifold (to the cooler) after a run I could feel both PS fluid and water on the underside of the cooler also. It emptied the PS reservoir in about 30 min.
Bob

There is no other way for PS fluid to get in the exhaust

Finally caught up with a friend who is a Merc mechanic. Said he has seen this before but usually have water in p/s too. Expained I have a crank mount Johnson seawater pump and the pressure is not as great as the Merc pump so most likely the p/s return line has more pressure. Agreed.
Sure glad I don't bother putting my tools away.

Wally, I already tried that today and the results were somewhat inconclusive

Mbam, I'm not 100% sure it's in the exhaust BUT it is milky and no other leaks in sight. Engine looks and runs fine.
There IS a p/s cooler under all of this...and the rear seat is NOT removable

I put ATF in my power steering so the red tint would indicate the leak. A small leak will dump allot of fluid very quickly, that stuff thins out when hot.