Just found oil in coolant and water in oil

fourkidsco · Post by **fourkidsco** » 26 Dec 2018, 20:20

Greetings one and all!

I have tried searching the vast internet, and have come up...confused. Many entires on this topic, but mostly for either older cars or much newer ones.

1 week ago, I checked my 2001 V70 XC and the oil was very low. Never saw an indication of overheating, but had to add 1.5 qts. Wasn't sure where it went. Everything looked fine at this point.

I broke the dip stick at the time, ordered a new one, installed today and noticed that there was water in the oil. Not much, and the oil didn't look like mayo yet. I checked the coolant reservoir, and there was oil floating in it.

So:

- oil in coolant
- water in oil
- oil level was still low, so not a major leak
- no evidence of overflow/bubbling in the coolant, so doesn't look like exhaust gases in coolant
- As far as I can tell, the car was not smoking (at least not majorly, didn't smell anything, no visible smoke)

I drained the coolant at the oil cooler in the back (looked darker than usual but clear and not muddy yet), drained oil and removed oil cooler. I dropped the oil cooler partly because I am limited in my garage and dropping the cooler will make it easier to bypass the cooler. My plan is to hook the coolant lines together, remount cooler, refill oil and clean out the coolant system (water and dawn).

After flushing the coolant system, I will refill with water and run for a bit to see if I get oil in the water or vice versa.

Am I on the right track? What else should I check?

Dave

Post by **abscate** » 27 Dec 2018, 00:55

1.5 quarts isn't too low, it's the hash mark distance on the dipstick. If you have the oil cooler biscuit (1999- on) off, pressure test the coolant side to see if it leaks

That is a unicorn failure here, though

More likely causes are head gasket or block failure. Compression test and exhaust gas in coolant test (definitive positive, soft negative) with dye solution are diagnostics steps

fourkidsco · Post by **fourkidsco** » 27 Dec 2018, 19:20

Admittedly a unicorn problem....and based on testing probably not the issue.

I am pretty handy around a car, but never done a head gasket before, I am struggling with the diagnostics.

I have read about pressure tests and compression tests. I know the cylinder compression test (done those) but a "pressure" test appears to be something different.

At this point, will the diagnostics be able to determine the difference between a bad head gasket and a cracked head? What else could it be? I know I would need to take the head in for testing anyway...why not just yank the head and get it tested?

I am wondering if I should just take it to my local mechanic to do the diagnostics.

Based on the results of testing, if it is the head gasket, I will do it myself. I found tutorials for older 5 cylinders, but not for the 2001 V70. Is there a major difference?

A pointer in the right directions for information would be gratefully received!

Post by **jimmy57** » 27 Dec 2018, 20:52

Before you do any serious worrying you need to take the hoses off the oil cooler on the back bottom of oil pan and use something to couple them together. A section of 1/2 conduit works or you can take hoses off at their upper end and use a loop of 5/8 heater hose (1/2 conduit is 5/8" OD to fit in the 5/8 ID hose just to dispel the confusion) on those fittings. Then put water back in it and run it a bit, a few miles with new oil would be great. If oil comes out of the coolant hose pipes on cooler then you have your answer. Plate and fin oil coolers corrode just like radiators and heater cores and the oil pressure can push oil to coolant and once car engine is off the coolant pressure can push coolant the other way into oil. It is an increasingly seen problem, but not epidemic, on the 99 and later Volvos.

fourkidsco · Post by **fourkidsco** » 27 Dec 2018, 21:21

I bought cheap oil for a test run (Rotella was on deep sale), will join things up and run it to double check...figure it is the only thing left I can do for the moment. will flush the coolant system out as well to clean things up.

If that fails or water shows up in the oil again, will probably take it in and pay someone else for the diagnostic work as the tools I would need would cost almost as much

Thanks.

Post by **cn90** » 27 Dec 2018, 22:08

If jimmy is correct, then the solution is:

- New Oil Cooler is about $60. Check to be sure PN 9497225 is for your car.
https://www.rmeuropean.com/Make/PartNum ... ch=9497225

- At this age of 18 years old, it is a good idea to replace the hoses too.

- Then flush coolant.

- Do an oil change.

- Periodically, monitor oil/coolant levels for any mixing.

Post by **jimmy57** » 27 Dec 2018, 22:24

oil cleans out of cooling system really well with Cascade auto dishwasher powder or liquid. It cuts grease and oil and it doesn't suds up and it rinses clean. That is exactly what it is made to do since that is what dish cleaning requires.

Post by **SuperHerman** » 27 Dec 2018, 22:29

Bypassing the cooler to see if it has an internal failure is an excellent diagnostic solution. All I would change is using some coolant dye added to the coolant/water blend. I assume if it finds its way into the oil it will show (a small leak in a water environment may just boil off). Not needed but if you have some in your shop supplies would not hurt.

Are you asking the difference between a compression test and a leak down test or a coolant system pressure test? As for the latter, one just pressurizes the coolant system (usually around 15psi) with air and and any leaks become visible as coolant will find its way into where it should not be, the leak, if there is an issue. There is a gauge that tells you the pressure level and once pressurized it should hold. I think one can get these on loan at some of the chain stores.

As to the compression test and leak down test - think of it this way. The compression test generates its air pressure from the pistons going up and down while the leak down test has air coming from an external source (air compressor). The leak down test has all the valves on the tested cylinder closed and the piston at a certain position. Based on how the air escapes one can judge the condition of the tested piston (usually the testing device has graded zones, but there are charts). If a valve(s) are not functioning to specification (fully sealing) one will hear leaks from the intake and/or exhaust side. On both tests a weak head gasket will show lower compression. One tests all the cylinders for uniformity which is what is most determinative.

fourkidsco · Post by **fourkidsco** » 29 Dec 2018, 11:21

Thanks for the explanation! That really helps...

Today I decided to check the plugs and I may have discovered where (some of) my oil was going.

#1 was clean and dry, plug looked fine, a little wide on the gap but ok.

#2 however, was full almost to the top with oil.

#3 had about 2" of oil, #4 & #5 had about and inch each.

While the car had felt a tad sluggish, we were getting OK mileage before this, so not sure how to interpret this.

I know this is a cam cover leak, but would this have any bearing/indication on my oil in water/water in oil issue?

Post by **jimmy57** » 29 Dec 2018, 12:24

Oil in spark plug holes can be spilled oil and oil cap gasket. Those causes are more common that leaking top cover to head seal.If you see rubbery silicone sealer oozed from that seam around head then the seal between the two parts goes to top of the list for reasons it leaks.