Hello, I have recently bought a 1998 v70 awd. Great car, love the low rpm boosting but have recently encountered a few problems. I am a college student and hoping to fix issues next month(may) between the end of finals and the start of summer session in June. I have diagnosed as follows based on what I have read on this forum but it would be great if someone could confirm.
*The main problems include brown sludge(oil) in the expansion tank, which is leaky and loosing coolant as well. There is also a similar sludge in the dipstick, I drive short distances to class and i beleive it is simply condensation. There is also a slow oil leak under my car which i beleive to be coming from the dipstick tube and/or oil cooler lines coming from left side of radiator(primarily top line). I really hope this issue is not the headgasket, and I think it is simply a rupture in the radiator where the oil is mixing with the coolant and because of a clogged pcv system, the high pressured oil is being sent into the coolant system. i plan on doing a coolant flush, oil change, changeing radiator and expansion tank. What else should I do, oil cooler lines are expensive and since leak is minimal it is not on the top of my low-budget list. Sorry if this post is too long as I am new to the forum. thank you for sure help in advance-Tommie

 

I'd make sure there is no head gasket leak first.

 

Thank you for the quick reply. How do I confirm this, compression test? There is currently no smoke coming from the exhaust or anywhere in else in the engine compartment and I removed two sparkplugs, both of which looked fine. I have yet to drain the oil, but the filler cap does not have any sludge, only dipstick. Thank you again

 

Cylinder leakage test or combustion leak detector. It's a kit with a blue fluid that turns green/yellow when it comes in contact with combustion gasses. You put the fluid in a tube that draws air from the coolant reservoir through it.

 

Ok I have heard of this system, I will attempt it as soon as I have time. Thank you for your help!

 

As you say there is no sludge on your filler cap, doubtful that head has gone. There is no way that oil can mix with coolant in your radiator, no oil goes to the radiator, and if you have an oil cooler, the that is cooled by airflow, it sounds as if you have blocked oil breather tubes and filters,check those out.

 

Start the car and let it run for a few minutes so things mix up. Drain the oil first. If the drained oil looks good coolant is NOT getting into the oil system. If an oil change is not due, put the oil back in the motor.

Next, drain the radiator. If that looks fine, add the coolant back into the system. Drive the car on the freeway for 5 minutes. Pull over and quickly check the coolant expansion tank. If it is trying to overflow, you likely have a head gasket breach.

As for your oil cooler line leak, that will only get words real fast so don't count on driving like that long.

 

@snaggapuss If the oil cooler is cooled by airflow, does this occur in the radiator? and if not why are there oil cooler lines(obv filled with oil because they are leaking it)coming from the left side of the radiator. And I will be replacing the pcv as soon as possible which hopefully should releive some pressure.

@rspi Alright I will also do the oil change asap, but for the coolant inspection what do you mean by "trying to overflow" can you see the fluid being pushed towards the top of the tank. I have a very small hole near the line that connects to the thermostat an will replace the tank soon, so when the pressure starts building a little fluid begins to push out of this crack.

Thank you both for your time, much appreciated.