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Curdl engine oiling

About a 1000 miles after changing the oil in my '97 Volvo 850 (120,000 miles)the oil goes through somesort of change. When checking the oil if the engine cold, the dipstick has whitish globules of oil on it, as if the oil is curdling. I have changed the oil 4 times in the last 8000 miles, and it’s happened each time. The engine runs fine, the power is the same, the milage has stayed up at 27 mpg.

What could be getting into the oil and what can be done to correct this problem?

Any suggestions would be appreciated.

Misha Pavlov

It sounds like you have a breached head gasket, resulting in coolant contaminating the motor oil–and that is not good. I strongly suggest that you have your mechanic do a Leak-Down Test a.s.a.p. in order to determine if you have a failed head gasket.

If you do have a bad head gasket, then you will have to decide whether this 13 year old car is worth repairing–especially in view of the cost of repairing Volvos.

Excessive engine “blowby” will also cause your oil to curdle. This is the result of rapid ring wear or sticky rings caused by too few oil changes.

A good mechanic will do a Leak Down test and compression check to identify what exactly is the problem. I would not keep driving it in the condition it’s in.

It sounds like there’s water in the oil. It could be from the cooling system, as VDCdriver suggested, or it could be condensation. Do you do a lot of short trip driving?

Have you had to add coolant lately?

Have you checked the coolant lately?

Thanks All!
I’ll have my shop do a Leak-Down Test, a compression test if needed and then go from there.

If the leakdown test passes make sure the mechanic checks your thermostat. It may be stuck open or not there at all. That will cause major condensation in the engine if it does not reach the proper operating temperature.

Where do you live Misha?? In severe cold, this is somewhat normal…Have the PCV checked. This valve is what vents your crankcase and prevents moisture build-up…

Check the PCV valve and also make sure the vacuum port and hose to the PCV valve are not clogged.

I took my Volvo to my mechanic (he’s a volvo specialist) and to my great relief, he determined that the problem is minor - the oil curdling occurs in and is limited to the sleeve for the dipstick due to condensation - the dipstick is right behind the radiator and this cools the sleeve more than other parts of the engine.
Thank you all for your consideration and your replies.
Misha Pavlov

I hope that your mechanic is right, but I have to say that I am skeptical of his explanation.