Spec Boxster Build - 986 Forum - The Community for Porsche Boxster & Cayman Owners

seningen · 04-27-2018, 02:52 PM

Quote:

Originally Posted by Quadcammer

blown AOS resulting in a broken ring?

I'm thinking that's the case -- was there any smoke out the back?

Mike

911monty · 04-27-2018, 03:40 PM

Let's try this one. Cracked cylinder/head #4/5 ? resulting in coolant in the oil. Oil filter is downstream of the oil pump so sees pressure not vacuum. Coolant saturated the paper filter media which swelled closed causing high DP across the media resulting in element collapse. Excessive vapor from coolant in the crankcase overwhelmed the AOS resulting in failure.

AZ986S · 05-01-2018, 11:31 AM

Quote:

Originally Posted by 911monty

Let's try this one. Cracked cylinder/head #4/5 ? resulting in coolant in the oil. Oil filter is downstream of the oil pump so sees pressure not vacuum. Coolant saturated the paper filter media which swelled closed causing high DP across the media resulting in element collapse. Excessive vapor from coolant in the crankcase overwhelmed the AOS resulting in failure.

Failure mode #???

Yeah was going to say filter is post pump. I can’t think of another way that the oil filter collapsed other than it absorbed coolant/water. These are not designed for separating water. Maybe a synthetic media filter would have done better? I.E. spin on.

The other question is: did the coolant in oil make the AOS fail? Funny that there was no smoke but there was a ton of oil in the intake...

I’m thinking more and more that the AOS didn’t fail, that is was just oil starvation caused by the crushed filter, destroyed / spun bearing somewhere?

Topless · 05-01-2018, 07:22 PM

I'm guessing failure of the engine oil cooler or an internal freeze plug causing intermix> collapsed filter> blown AOS> Oil in the intake. The motor is full of goo but if no metal debris it may be salvageable.