Brown motor oil

[gckdonahue]

I have a 1989 OMC 4 cyl I/O. When I went to change the oil it came out the color of heavily creamed coffee. It did not seem to be over filled and did not smell of gas. How bad is it?

 

[vinney]

Re: Brown motor oil

Water in the oil. Leaking riser,manifold,riser gasket. You are injesting water thru the exhaust. Vinney OMC replace risers and manifolds every 6 years.

 

[Bondo]

Re: Brown motor oil

Ya, sounds like Water..... If Vinny's right, That'll be the Lesser of the possible evils....

 

[gckdonahue]

Re: Brown motor oil

I would think that if it was water it would seperate out. Also, I had my wife smell it (I have a cold) and she says she smells gas. That would probably be the worst case scenario?

 

[vinney]

Re: Brown motor oil

You can go to any large diesel dealer Cat, Cummings, Volvo and Mack They sell an oil sample kit that is sent to a lab. They will tell you every thing in that oil good or bad. Its about 30 dollars. We use Cats oil sample kits. V

 

[Trent]

Re: Brown motor oil

Hey Vinnie.. Iv got a couple of suppliers that have kits for half that. (Retail)18.95<br /><br />But Vinnie has it right. Change manafold and risers. If you dont like that idea then pressure check them...then you will have to replace anyway.<br />Saltwater boats get about 4-6 years on them and freshwater boats almost double that.

 

[vinney]

Re: Brown motor oil

I have tried the cheap kits and they lack the data of a full blown lab. The better labs give you alot more info and if they find a problem they call you asap. I really dont have confidence in that kit you buy at the local boat supply co. I have to have confidence in my tools and equipment and this is a tool we use alot. Vinney

 

[flashback]

Re: Brown motor oil

my feeling is, if you have light cream colored oil in your engine, you don't need a kit.. the block is busted or a seal,gasket,has gone bad....... oh yea maybe the heads........in any case, it should not be hard to find the prob. good luck ....................

 

[vinney]

Re: Brown motor oil

The reason for the test is it was stated that they didnt know what was in the oil (gas or water) I dont guess I use tool to make an accurate diagnosis. The owner of the boat stated they didnt know. I dont know from were I sitting . A tool can prove or disprove if its gas or water. v

 

[vinney]

Re: Brown motor oil

You dont need any thing broken,cracked,blown out to have water in your cylinders.

 

[Trent]

Re: Brown motor oil

Vinney.....Im in aviation and WE want all the info we can get! They do call if its out of range. I do these kits all the time. But its more aviation related. Want to try one just for the heck of it Iv got a few in stock. Trentcr@hotmail.com See if ya like it? Id like to see what it does in the marine industry..You too Cappy..

 

[foresr-grump]

Re: Brown motor oil

I have just discovered tan oil in my OMC 140 and the riser/manifold replacement seem to be logical. Is it also possiable that the head gasket is leaking between the water passages and the oil return? however, I don't see any water in the combustion chamber.<br />Also, any source for replacement parts?<br />Thank you for your help.

 

[SS MAYFLOAT]

Re: Brown motor oil

Hi Webster01,<br /><br />If you still have the oil, put it into a clear or semiclear jug like a milk jug. Let it sit for several days. If it is water, it will seperate and the water will be on the bottom. If it is gas, it will take alot longer to seperate (if it does at all). If you have a closed cooling system, and the oil is gooey and somewhat stringy, it is anti freeze in the oil. That stuff is nasty!<br /><br />Trent and Vinney are good, as a matter of fact REAL GOOD! They have helped me find answers when others just scratched their heads. (Now if Trent would let me know how to squeeze out some precious horsepower from my 350 without squeezing my bank account)<br /><br />For a Redneck Buckeye like myself, this is how I check my oil for obvious contaminants. Also welcome Aboard to the Forum.

 

[gckdonahue]

Re: Brown motor oil

Thanks for all the info so far, its been a big help. But I am still a little confused. I do still have the oil - in a milk jug no less and there is a liquid seperating out in the bottom. I changed the oil on Saturday. However, it has a definite gas odor to it( my head has finally cleared). If it proves to be mostly water , how do I pressure test the exhaust manifold. Or if it is gas does that mean a cracked block or bad head?

 

[SS MAYFLOAT]

Re: Brown motor oil

If it is possible, try to extract the liquid that is on the bottom, this should be water since water is heavier than pertoleum. Gas weighs lighter than the oil, so it should be on top of the oil. That is why you get the gas smell.<br /><br />Gas in the oil will come from only one place which is the carb. A sticky/float level, incorrect jetting, choke stuck in the closed position, leaky gaskets, or a remote possibility of a weak ignition problem can cause gas in the oil. <br /><br />How long has it been since the oil change before this one? and about how much water was in the bottom of the jug?

 

[gckdonahue]

Re: Brown motor oil

I will try to remove the liquid. There was about 1/2". The last time I changed the oil was last fall. I only had about 20 hours on the boat this summer.

 

[flashback]

Re: Brown motor oil

ssmayfloat, carb is one place, thats true, but also a mechanical fuel pump can let gas into the oil if the diaphram is damaged......by the way webster, the fluid in the bottom of the jug is water, if the fluid above is oil.

 

[ICEMAN]

Re: Brown motor oil

In my experience, I have not seen gas mixed with oil, turn it milky. I have seen gas dilute the oil so it looses it's viscosity, but not turn milky. Water in the oil, turns the oil milky as the oil pump blends it together. The smell of gasoline in the oil is not a major problem, oil will pick up some gas smell the longer it is in the motor. That's one of the reasons it should be changed at least annually. Checking the oil with the test kit does provide you with a lot of information. Those results have good and bad points.

 

[foresr-grump]

Re: Brown motor oil

A quick and easy way to check for water in the oil is to pour it through a piece of fine cheese cloth, the water will remain in the cloth.

 

[flashback]

Re: Brown motor oil

if your oil looks like a chocolate milkshake, it has water in it,period.......... fuel will not turn the color of the oil.