I got a jeep from my coworker and he said the motor needs work well first thing I did was check the oil and it looks milky like water mixed with it. I know that's not good and I know absolutely nothing about this stuff just curious what could be wrong with it.

 

After reading your other thread about a rough idle I'm leaning towards a blown head gasket. It's a 1999 right?

 

Head gasket or cracked head, depending on how long it's been like that for it could need a full rebuild or engine replacement. The problem happens when the water is substituted for oil where it's most required. Instead of a proper lubricating film, the metal parts just score and scratch against each other.

 

Time for tear down, water in your oil is never good. A little bit of milky film on your filler cap happens during the winter due to condensation and is not unheard of, but if your oil on the dipstick is milky you need to pull the head and go from there.

 

Yes its a 99, I knew something was wrong with it but not sure and I don't know much about engines so my cousin is a mechanic and he's going to pull it apart this weekend and hopefully get to the bottom of the problem

 

Milky oil can also be caused by coolant leaking into the oil. As said before, cracked head.

 

Mine was brown but now milky....new radiator did the job.


I would check the dip stick and oil cap.
Sorry to say this, but if the cap looks like this....you are probably .
New head or head gasket is in order.



A leak down test will tell you if you REALLY have a cracked head/gasket.

GL bro.

 

Leak down test will only show bad IF the crack is into the combustion chamber.

There are many ways the crack or blown gasket can get water in the oil.

 

.....and not into the cooling system?
Wonder where else.....beside the cooling system.
Only place i can think of is wiper/washer fluid .

 

The head has lots of coolant passages AND lots of holes leading fown to the crankcase (pushrod holes, drainback holes etc..) ANY place that allows coolant to get into a hole that leads down into the crankcase can get water in the oil.

And - oil can also get mixed with the water.

My commet was someone said a leak down test will always show a gasket crack problem. The leak down test can show it BUT ONLY IF IT'S AFFECTING THE CHAMBER. THINK ABOUT IT!

IF you put washer fluid in your oil you shouldn't be allowed under a hood!

 

I thought washer fluid was to clean your oil?!