S90 water in oil, runs great Topic is solved

TerrDawg · Post by **TerrDawg** » 30 Oct 2017, 20:48

Bought the cleanest S90 I've ever seen, clean inside and out, I checked fluid, put a battery in it and it drove great, lights on the dash were off and on, no check engine light tho, ABS, Coolant level, etc. drove 8 miles noticed the water level gauge come on and stay on, temp started rising so I stopped. Milk for oil, bummer
Question is, it still ran very good, previous seller said he had head work done recently and wouldn't do it again so I bought it... Is it possible for water/coolant intrusion via an oil cooler that uses the cooling system to cool/warm the oil? Or, is there any other reason besides head gasket?
Thanks Volvo Friends,
Terry

Post by **mrbrian200** » 31 Oct 2017, 01:57

TerrDawg wrote: ↑30 Oct 2017, 20:48 Is it possible for water/coolant intrusion via an oil cooler that uses the cooling system to cool/warm the oil? Or, is there any other reason besides head gasket?

I believe the answer to that is yes. I'm not sure all S90s were equipped with the crankcase oil cooler integrated into the radiator. If the radiator has a total of 6 hose connections then yes it is possible.
That would be sad if the PO or their mechanic misdiagnosed and replaced the head gasket to no avail then gave up on an otherwise mint condition car.

Post by **precopster** » 31 Oct 2017, 06:59

My 960 had a front mounted air cooled engine oil cooler. I believe that didn't change in successive years up to the S90/V90 so the answer is NO. Head gasket is most likely culprit.

Post by **jimmy57** » 31 Oct 2017, 07:08

The oil cooler on that year model is the adapter the oil filter seals against. You can disconnect the water hoses and then put them together with some sort of connector. Hardware store may have a barbed bras or plastic fitting that would do. Then while you flush the cooling system with Cascade auto dishwasher soap, you can run engine and see if oil comes out of the hose nipples you took coolant hoses from.
If that proves to be the source (almost has to be) then the big nut on the hollow stem oil filter screws onto is loosened and the cooler slides off.

lummert · Post by **lummert** » 31 Oct 2017, 07:59

I saw this in a Ford diesel truck article. Bypass coolant hoses, place tampons in the hose nipples, run engine. If there is an oil leak the tampons will catch it.

TerrDawg · Post by **TerrDawg** » 31 Oct 2017, 09:55

Great info, glad I didn't just tear into the head before asking, never heard of a oil cooler and coolant mixing to use one another to stabilize temps ... But then again I'm an engineer for trains, not mechanical egghead (uh, no offense if you're an egghead)

lummert · Post by **lummert** » 31 Oct 2017, 10:06

With a leaking cooler coolant will seep into the oil after shutting off the engine. Pressure is still present in the cooling system.

Post by **mrbrian200** » 01 Nov 2017, 11:47

If you google 'Volvo s90 water in oil' there are multiple references to this problem, and it seems to apply to vehicles equipped with an optional engine oil cooler from the factory. There are two versions of replacement radiators for this year/model, both with and without an engine oil cooler, same type of internal cooler as the trans cooler, but on the opposite side.

TerrDawg · Post by **TerrDawg** » 01 Nov 2017, 18:40

Findings: disconnected oil filter lines at oil filter, only water came out (dirty water no coolant) let engine run 20 seconds and only water exited. Then I noticed coolant on ground at approximately midway, removed exhaust heat shield and followed lead to mid head area. Since there was just head work done, I added snake oil to the new coolant added fresh oil and so far no more leak, will change oil bunch more times until clean possibly new radiator... we'll see
Thanks for the input you guys are great
Terry

lummert · Post by **lummert** » 01 Nov 2017, 20:04

Maybe an external oil cooler would do the job.