Oil in the Coolant Mystery- Over.

[Vegas Boy]

I posted a while back about a vexing problem I was having. There was definitely oil in the coolant. Normally, you start clutching your bank book thinking about blown head gaskets or the dreaded cracked or pinholed block. Anyways, you think the worst. But the car ran great. WTF?

I drained off some oil and sent it away to Titan Checkup in the little plastic bottles you buy at Pep Boys ($14, a good investment). To add to the mystery, oil came back perfect, no coolant in the oil (they check for about 8 diff things). Now I am really stumped. Maybe they screwed up, did it again, came back perfect again!!

So, last week I had the car (91, RM NOS, RM SS exhaust, 17/18 Work Anhelos, misc other stuff, 54,000 miles) in for major service at Factor X at the Las Vegas speedway, and here is what they found- (drum roll, please) ...........nothing!

The compression leak down was less than 10% cold, which Mike said was excellent. The motor was tight as new. So, they flushed the coolant and all was fine. Ran it a while, still fine.

So, after all the discussions, phone calls, opinions, theories, etc- it would appear that the dumb ass prior owner or a dumb ass dealership/service station dude at some point put a quart in the coolant bottle.

Sometimes the obvious answer is the answer.

 

[I Grok NSX]

Doh!

 

[4AU4LIFE]

Good for you !!

 

[LJSB]

One way to get oil in the coolant is to have someone drain the coolant into a container that they used for oil and then put it back in the car. Most repair shops have black plastic pans for oil and green ones for antifreeze. Somewhere may lurk a lazy person who will not look for the one they need when changing a coolant hose or thermostat and use the one meant for oil or some other contaminated container.

 

[nsxxtreme]

Either that or you once had a blown head gasket and noone flushed the radiator after they fixed the problem. This is what is currently wrong with my beater car. I have oil in the radiator but no water in the oil pan.