Testing for Coolant in Engine Oil

[Married2Allis]

I see Part Time Pete's post (say that 10 times fast!) about testing coolant with test strips. Obviously you don't want to run contaminated coolant. And obviously the reverse is bad -- coolant in the oil. I have two questions:

- what amount of engine oil or combusted fuel in the coolant will do damage and to what?
- how do you test for COOLANT in the OIL?

Bret

 

[Michael Soldan]

I believe that you have two different viscosities which will sort themselves out, so , if you put the liquid you drain out of the crankcase
in a clean clear glass container and let it sit you will see the oil float to the top and the coolant remains at the bottom. It may need to
sit for a day or so but you should be able to see if there are two distinct fluids. Likewise drain some coolant into a glass container and
any oil will float to the top. Determining how much will depend on your scientific approach. Measure an amount of volume and then measure
how many millimeters of oil is on top of how many milliliters of coolant and you should be able to come up with a ratio. I don't think the
ratio is important,if you have oil in coolant or coolant in oil you need to be looking at the entry source be it a head gasket a pump or even
a trans cooler can put trans oil in coolant, regardless you have a problem that needs solving

 

[Married2Allis]

I typically check the oil by draining the first gallon into a glass jug then look on the bottom. But doesn't condensation (water) also collect in the crankcase over time?

 

[Steve@Advance]

I believe the coolant test done with the test strips is to check the level of corrosion inhibitor left in the antifreeze. On larger trucks and equipment that holds a lot of coolant, it is cheaper to add the inhibitor than replace the antifreeze.

If there is oil in the coolant, it will find it's way to the top of the radiator. Oil in the coolant won't really hurt the coolant, but it will cause the hoses to deteriorate. No real way to get it out other that a thorough flushing with soap and water after repairing the source of the contamination.

There is also a test for combustion gases in the cooling system, but this is a test for a leaking head gasket or cracked head, not coolant contamination.

As for coolant in the oil, that will usually show as condensation under the oil cap. on the upper end of the dip stick, etc. You can have an oil sample analyzed. That checks for all types of contaminates.

 

[gene bender]

When you pull the drain plug the coolant will come out first if the engine hasnt ran for a couple dys.I
replaced a headgasket that was leaking anti freeze into the pan bearings were ok but there was lots of
coolant that had leaked bearings looked OK realy permanent anti freeze wont bother it would take yrs and
heavy hot work to probably ruin the bearings quit worrying

 

[jacksun65]

If you have an oil analysis done they will tell you and explain the results.

 

[Mike M]

What happens with antifreeze in the engine oil is it will literally eat into the bearing material.

 

[BarnyardEngineering]

If you get the engine up to operating temperature on a regular basis, what little moisture that collects from condensation will boil off and go out the breather as steam. You won't even see it go because there is so little of it.

You can see coolant in the oil because usually it's a pretty major amount.

 

[donjr]

It's easy enough to check. Let machine sit for a few days- the longer the better, but overnight may be enough. Put a pan under
the crankcase drain and crack the plug a bit. Don't take it out- just turn it enough to start dripping. You'll probably get a
bit of oil, but if you have water in the oil, it will start dripping water. The water (or coolant) is heavier than the oil and
will separate overnite and go to the bottom, so the first liquid you get will be water. A few drops isn't too bad, but a good bit
may be rather serious and needs a mechanic.

 

[Longknife]

ANY coolant in the oil or oil in the coolant is TOOO MUCH!!!

 

[Greg1959]

When I worked in a Oil analysis lab, we used a test similar to this
kit....
Poke here

 

[ditchwitch]

We use Blue Point combustion leak tester really easy to use and works great

 

[Gene Davis (Ga.)]

Oil in the coolant will cause a film on the radiator flues and will slow the heat transfer rate somewhat.

 

[caterpillar guy]

If you let it set for a couple of days here you will have frozen water right now if it is just water. Other wise as Gene said it takes a fair bit to be a problem. And if there is oil going into the water. I would not get to excited unless it was a lot. I drove a semi home with the oil cooler leaking into the water. I had to add oil in OH to get home. This was from NC near Charlotte. The biggest problem was keeping it cool. I was running about 200 by the time I got home.

 

[Heat Houser]

Go to any dealer and ask for an engine oil sample kit. Deere calls them OilScan as a trademark.
Typically, the crackle test is used for checking for water/coolant in the oil.
You need to look at the elemental analysis and look for the ppm of potassium and sodium.
These two elements (part of antifreeze) will start showing up long before the crackle test can detect it.
Coolant etches the rod and main bearing inserts. Ventilation of the block is the result if ignored. (Rod poking a hole out the side)
Good luck