29 April 2018

Did another long back country drive, finding new and wonderfully twisty roads off the beaten path. Even on a Sunday, when motorhomes and pickup trucks with dirt bikes clog the roads heading back from the desert, there are still a few roads to be explored. About half way through this drive, the little voice in my head asked, “Do you smell something?” Me: no.

A bit later, “Are you sure, it smells like oil.” Me: Yeah, but it’s really faint and probably isn’t even coming from my car. It could be a truck and I don’t see any smoke. As I neared home, however, the oil smell had become unmistakable.

Pulled into the garage and the line of oil down the street delivered the message in no uncertain terms that something was up. The bottom and back of the drivetrain, and all the suspension and the rear of the car were covered in oil, so the immediate goal was finding the source.

Started it up and there it was, coming from around the oil-to-coolant heat exchanger. After cleaning up the mess to get under the car without taking an oil shower, a closer look found it was coming from the inlet fitting on the oil cooler. The -12 AN fitting wasn’t loose; it was the bolt-on adaptor it was screwed onto that was leaking. Oddly, the Torx screws were tight, so it seemed like the gasket must have given way after, what, five years?

After removing the fitting, it turned out that it’s sealed with an O-ring and it seemed like it had gotten pinched – or so I thought. It wasn’t until I pulled it out of the groove that I found there were two O-rings! The only thing I can think of – given that there’s only room for one O-ring – is that the assembler must have reached into a bag of O-rings and not noticed that two were stuck together. Amazing that they remained sealed for as long as they did.

I’m going to call the seller to see if they’ll give me a free replacement gasket set if I casually mentioning that the only reason I didn’t trash this engine was the 8 quarts of oil in the dry sump system. When the tank was drained before removing the fitting, it was a bit shocking to see that only about two quarts of oil were left. I think the leak started very gradually which is why it didn’t become suddenly obvious. Seeing the solid line of oil down the street, I doubt it would have lasted another 20 minutes. Yes, the ECU should catch the low oil pressure with a rev-limiter and a warning message, but I don’t want to test that. Close call though.