Replaced exhaust cam seal, driver side, LHD car

[Allgonquin]

2004, 270K miles (yes!) Car developed a significant oil leak almost overnight. Seemed to be coming from the driver's side of the engine. Could not see anything from on top, and she's always been rather oily underneath, above the belly pan. Took it to a non Volvo specialized indy shop with a lift and asked them to see if they could determine where the leak originated. Best they could say was "up towards the valve cover". OK. So after I got the car home, I did the rubber glove test on the oil fill cap, nice vacuum. Good, at least that is not the cause of a blown out cam seal. So I gambled and bought one seal, for the exhaust cam, driver's side. Just finished the job. A bit fiddly to get some of the bolts out for the bracket holding the engine mount bracket, but I got there. Pic shows what I found. Replaced seal, fingers crossed that this takes care of the leak

[Xfingers]

The vacuum from your rubber glove test only shows the PCV IDLE circuit isn't plugged. There's another BOOST circuit for PCV gases when the engine is under load like if you're accelerating up a steep hill. I blew out a cam seal going up a mountain pass after my 2002 XC70 had been showing suction with the rubber glove. Hopefully your boost circuit isn't clogged but there's probably a reason why positive pressure in your engine crankcase (as opposed to the negative suction at idle) blew out your seal. Just something to keep an eye on and at 270k miles, it wouldn't be a surprise if your PCV was due for replacement. I've got strong suction at idle on my 2007 XC70 but I'm having to add a significant amount of oil after hard driving. At 220k miles, I'm thinking maybe it's the PCV system. Good luck with the new seal!

[Allgonquin]

Fingers crossed, but looking good. It's been a week and the belly pan should have started to allow a leak if it was leaking at the previous rate - so far the garage floor is good! As for long uphill runs in boost, not at all a common occurrence in this car.

[vtl]

Any acceleration or even cruising steady at high speed is boost.

At 270k the cylinders are tapered upwards, the compression rings are worn, too. The sump gets much more of blow-by gasses, so good working PCV is even more critical than it was with a new engine block.

I measured compression rings in couple of engines with 220k on odo, both were out of spec in the lowest cylinder point, much worse in upper, tapered half.

[Allgonquin]

Still dry now on the 28th. Clearly the seal was the cause of the leak. Not saying the car doesn’t have blow-by….I’m sure it has “age appropriate” wear on the cylinders. PCV was done at 185k so yes, it’s probably overdue. It gets Mobil 1 every 3k which should help. Anyway, she’s one big failure away from the recycling yard. Paid $4k for her in 2014 - I’d say I’ve gotten my money’s worth!