mausc

I'm picking up where I left off last fall....

http://www.offshoreonly.com/forums/d...water-oil.html

There wasn't much I could do back in the end of November so I'm picking up the pieces now.

Changed the oil yesterday morning (with the milky mess) and splashed her. Ran the motor on the trailer a bit waiting for imminent destruction. Didn't happen. Decided to go ahead and launch and putt putt around the creek. Everything ran as I remembered it. From the creek to the main waterway is all 6 MPH and I just pretty much ran her between idle and 1200 RPM. No major devastation. She did stumble a bit here and there (vacuum leak???) but otherwise ran fine. Temps ran around 170 once warm and oil pressure stayed around 20 PSI. Oil Pressure has always run kinda low. Perhaps because of oil/water emulsification.

Got out to the river and got her up on plane. Didn't go crazy. Just some basic cruising and turning around 3000 RPM. As I said before she ran pretty nice but I did notice an occasional stumble or roughness. This might have been there last year too before I put her up for the year and just didn't pay that much attention because I didn't think I had a problem. Now I'm hearing and noticing everything.

Got over to my house and got her up on the lift. Changed the oil again. Still milky but considerably less so. Too late to run again but I think I will at least get her idling on the lift over the next day or so and take her out localy again the next nice day.

So.... Recapping possibly scenarios from last fall, intake manifold, head gasket, and oil cooler were the main suggestions before assuming the block is cracked. How to proceed.

Oil Cooler would be awesome because I think it's pretty easy to change, but the logic doesn't fit. The cooler is effectively a log filled with raw water with heat exchangers inside. BUT... Oil pressure is higher than the water pressure. Id expect to see oil coming out the exhaust rather than water in the oil. I did just order a kick-ass Snap-On Compression Tester that should be here later this week.

Any suggestions on a diagnostic path to identifying the problem?

I'm all ears!

ThisIsLivin

Run a leak down test and see if you have air coming out of any water passages. Pull the thermostat and feel for air escaping.

mausc

Sounds reasonable. I'm gonna start with the compression check and see if I can find someone with a leak-down checker.

No one here as mentioned manifolds/risers. A guy here at work said he had a similar problem and that was the source. I can see bad manifolds allowing some water back through the valves (and not being enough to hydrolock) but how does it get into the oil? That would suggest bad rings. No?

4bus

iTrader: (4)

No, Water is thinner than oil, and under compression has to go somewhere. It goes past the ring and into the pan.

You mentioned it is missing, which makes me think you have water in the combustion chamber.

What exhaust do you have? Is it a salt water boat? What year, hrs, engine model?

blue thunder

Pull the plugs and see if some are steam cleaned. It definately sounds like exhaust leaking into cylinders. That missing is the engine trying to digest the water in the cylinder(s). Water takes up room in the combustion chamber so you don't get away running it the way it is for long.

1BIGJIM

iTrader: (1)

Start with the easiest. If you have stock exhaust manifolds, pull the risers off and look down and look for a trail of rust.

If that checks out fine, pull the plugs and do a compression test. You are looking for a blown head gasket. Leakdown test is not needed at this point.

You did not say how much you extracted when you changed the oil this week. Remember it only takes a little water to turn it to milkshake.

mausc

Boat is a 95 Formula 252 with a stock 454 Magnum Fuel Injection. Hours are 233. Mostly used in salt water. Previous owner seemed to have been really good with maintenance. Boat is spectacular condition, but I don't have detailed records of what's been done. I bought it last fall.

I read this comment on another site earlier today:

"Change the oil and filter. Hook up a flush and run the boat out of the water with the flush hook up. Take one of the oil filler caps off. bring the engine up to tempure. If there is steam coming out of the valve cover hole. You are ingesting water thru the exhaust Manifolds,risers, or riser gasket. "

I changed the oil and filter yesterday and ran it today, not on rabbit ears but on my lift with the drive lowered down into the water. I did check and steam did indeed come out of the breather tube.

I ran the engine at idle and up to 1200 RPM with the engine up to temperature. When I shut down I didn't see any milkshake on the dipstick. I'll check again in the morning.

I might be out to lunch but I'm really thinking I'm looking at manifolds and risers. I think I'm going to go order a set and pop them on. I don't know how old these are but I'm guessing they're far from new. Even if I have a bigger problem I don't mind having a new set to put on a new motor if it comes to that.....

blue thunder

If you have milkshaked oil, you will have steam out the breather. Simple as that. You will not see milkshake on the dipstick. The dipstick when removed passes last through oil so it cleans the milkshake off the dipstick. Remember oil floats on water. I agree on the manifolds and risers needed to be replaced. The center spark plugs will be steam cleaned most if the risers are leaking.

kubelwagonman

pull the intake,..,,if block is cracked yu will see it up right where the block meets the heads because the water passages are very close to lifter valley

sleek1

I agree with those that have suggested an exhaust riser issue. They are easy to pull off so take a look. The gaskets are cheap and probably need to be replaced anyway. Leaking riser gaskets are a common issue.