Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: milky engine oil
Posted by chris galschjodt on 05/02/13 - 9:04 AM
#1
Question. At the end of last summer the engine oil in my 2002 Johnson four sroke was starting to turn a milkshake brown. Fearing I had a head gasket leak I took it my ace mechanic and he said there was nothing wrong. He told me this was a result of not running the motor at speed which gets the motor hot enough to burn off condensation in the oil.I do alot of fishing and most of the time I'm putting around barely above idle. Does this sound familiar to anyone? Chris
Posted by Petrus on 05/02/13 - 10:43 AM
#2
I've seen cars with this symptom when driven short distances which doesn't let the motor run warm long enough. More commen in the winter though.
Posted by contender250 on 05/02/13 - 11:24 AM
#3
Is the oil turning white or is it just filled with fine bubbles that are not mixing? Even if you are running the engine for a lot of time at a low speed the oil should heat up enough to get rid of the milk shake appearance. However if you have run the engine for a while and still have the milk shake in the oil you have a leak. I would drain all the oil, let it drain for a good 24 hours, put new oil and filter, if the shake comes back you have a leak...Good luck
Posted by CES on 05/02/13 - 11:35 AM
#5
It's probably nothing more than condensation that's buil up in your block and mixed in with the oil.
A good day of running it hard or an oil change will fix ya right up. The heat in the motor will evaporate the moisture.
This is why it's always a good idea to change the oil before you put her up for the winter....it'll help prevent corrosion from forming inside the motor too.
Posted by chris galschjodt on 05/02/13 - 11:42 AM
#6
Thank you, Derwd. My mechanic told me pretty much the same thing. He also said this has become so common that they are designing the new motors to run a little hotter to prevent this from happening. I guess I'm going to have take her out and open 'er up more often. But I'll deal. Chris
Posted by Derwd24 on 05/02/13 - 11:48 AM
#7
As Contender suggests, and oil change and check shortly thereafter would be a very good idea. Small amounts of condensation will not show up as milky oil, so if you still have it happening, further investigation is needed.
Posted by CES on 05/02/13 - 12:55 PM
#8
Derwd24 wrote:
As Contender suggests, and oil change and check shortly thereafter would be a very good idea. Small amounts of condensation will not show up as milky oil, so if you still have it happening, further investigation is needed.
Sorry Dave,,,I guess I should have read yours and Contenders posts a little more thoroughly...
Posted by Derwd24 on 05/02/13 - 1:01 PM
#9
No problem Cliff, you may be right in that it just may need a hard run occasionally. But can't hurt to check for something more pressing just to be sure.
Posted by CES on 05/02/13 - 1:10 PM
#10
Derwd24 wrote:
No problem Cliff, you may be right in that it just may need a hard run occasionally. But can't hurt to check for something more pressing just to be sure.
That's what I was told to do with my BIG motor in my other boat...after I showed concern for a milky oil substance under the valve covers....they said I should do more cruising than idling.... so with that advice, I hammer it a little more often...lol.
Posted by BillDemers on 05/02/13 - 5:29 PM
#11
A pressure test of the cooling system would tell that the water is or isn't coming from the cooling system.
Posted by Petrus on 05/03/13 - 11:36 AM
#12
This is how it can look like under the oil cap:
http://m.flickr.com/#/photos/zutterbu...353753478/
Ask your mechanic to check the crankcase ventilation also. Might need to be cleaned.
Edited by Petrus on 05/03/13 - 11:47 AM
Posted by chris galschjodt on 05/06/13 - 11:54 AM
#13
Hi Petrus Where would this crankcase vent be on the motor?Thanks in advance, Chris
Posted by Petrus on 05/06/13 - 12:46 PM
#14
I don't know exactly how it looks on your motor. But here is a good explanation how it works.
http://www.sr20-forum.com/information...ition.html
I think you should be able to check if it works correct by remove the oil cap and cover the hole with plastic film. The film should not bubble up during idle, as ther should be vacuum. My guess is that water can't vent out if crank case vent is not working.
Note, I'm no expert at this, but I think condensed water should vent out this way. Best is to ask your mechanic if this could cause your problem.
Edited by Petrus on 05/06/13 - 12:52 PM
Posted by duf on 05/06/13 - 1:33 PM
#15
I just got a 4 stoke, so no opinion on an outboard, but had the same thing on my garaged CJ7, which had a 258 in it. I routinely changed the oil, and it would always turn milky in short order, Drove me nuts, and i had the motor checked for leaks at several different places because i didn't believe them. Bottom line, it was condinsation.
Duf