Mayonaise looking substance at my oil fill

Needs some help with this. I have a 99 Maxum with a 4.3L alpha 1 gen 2. Milky oil was found earlier in the season. Engine was drained, oil and water came out separate along with a bit of milky oil. Cleaned out, refilled, shop tested, lake tested, could not duplicate problem. They contributed it to my error with a engine flusher. Evidently I may have let the flusher on for a few minutes, with the engine off. (put the engine cover back together, cushions back on, etc). Shop told me to keep an eye on the oil level.

I have been keeping an eye on the oil level. Level seems fine. Boat has been running fine. I am out every other weekend.

Today, I decided to open the oil fill cap. I found a mayonaise type substance in my oil fill tube and cap, along with some condensation on the cap. Am I having a water issue again or what could be the explanation for this problem?

A side note, compression test was fine when the earlier problem was discovered. All six cylinders were firing normal.

Thanks for any advice.

Re: Mayonaise looking substance at my oil fill

Once there is water in the engine, you will be a while before you get every bit out. It will condense in the valve covers as the engine heats and cools. You can take the valve covers off and clean them out to help get it out faster.

Its not a huge deal unless its getting in the oil pan and thinning the oil.
Just watch it.

Re: Mayonaise looking substance at my oil fill

I agree with bifflfan,it's just residual condensation.But I would keep an eye on it.

Re: Mayonaise looking substance at my oil fill

If the oil on the dipstick looks good after a run, you're ok. I often see a bit of water vapor coming from the rocker cover vent hoses being drawn in to the flame arrestor.

Re: Mayonaise looking substance at my oil fill

Happens to engines that never had water intrusion, too. For example, the Dodge 4.7 V8... it's a common question on the Mopar boards.

If you've come this far, and that is the only issue after the big water issue: Congratulations. Clean it. Check it. Lather, risnse, Repeat. Enjoy boating!

Re: Mayonaise looking substance at my oil fill

Condensation occurs when the engine isn't running hot enough, and/or the crankcase ventilation system isn't operating properly.

It can also occur when the oil IS getting hot enough to boil out the water, but is either overwhelming the ventilation system due to excessive volume or plugged pcv valve or crankcase vent intake.

Don't dismiss this issue. Check your PCV system thoroughly..if no problem is found you MAY have more serious problems.

You DO have a thermostat in your engine? nothing worse for performance, economy, and durability than a cold engine.

Re: Mayonaise looking substance at my oil fill

Thanks for all the responses. Yes I do have a thermostat, the gage always gets up to about 1/2, never more, never less. In my opinion the motor is getting hot enough? Motor runs fine, no issues. I do check oil level regularly, and it has been good all season. I had it to a large lake in PA a few weeks ago, where I could run it wide open for a long period of time, still no issues.

I am taking it for winterization toward the end of the month, I will let the pros look at this one, again. I fear there is another issue somewhere, but they could not duplicate the problem, when water was found originally?

With the condensation issue, should I take the motor cover off and expose the motor to the sun, throughout the day? Will that help dry things out?

Re: Mayonaise looking substance at my oil fill

mwilliams43 said:

......

With the condensation issue, should I take the motor cover off and expose the motor to the sun, throughout the day? Will that help dry things out?

Click to expand...

That'll dry the outside of the engine and the engine compartment but won't do a thing for moisture inside the engine. A half hour or more run at speed will evaporate most of it.

Re: Mayonaise looking substance at my oil fill

next time out just pull the oil filler cap and run it for most of the day. This will speed up the evaporation of moisture in the engine.