Oil cooler - How to test?

[kth286]

It might be easier to take it to an old fashion rad repairer to test as they should have adapters etc.

That's a good idea.

As it looks like an obvious hole exists somewhere, what about just trying to tape over the holes (masking tape perhaps) and merely blow into it and see if anything obvious reveals itself.

 

[jefrs]

On the E32 (3.2 V6) engine it is much easier for the oleo-radiator to fail than the oil cooler, this will put tx into the water and water into the transmission fluid, very bad news.

Places for water to commonly mix with engine oil are water pump, oil cooler, and cylinder heads. Cylinder head failure has unique and obvious symptoms (white smoke). A dying water pump can seize and rip the serpent off.

My failed oil cooler just needed a new gasket. As you can see, it is pretty simple and robust. Mind you, it was leaking oil onto the fan belt not water into the oil.

I wouldn't mess about trying to find a leak, I would never trust it now, just replace the oil cooler and gasket.

K-Seal.
This stuff really does work and I've seen no more mayonnaise around the oil filler cap since dropping it in.