I have a puzzler and a theory I'm interested in feedback on. Didn't find any prior relevant posts but maybe someone else has seen this (there are no one-offs in the B230 at this point!). I've been diagnosing a persistent, slow oil leak for a couple of years now on my '93 945 with 265K on it. The oil has been changed 32 times in the 130K I've owned it. It's well maintained and runs well though I cannot vouch for the maintenance ethic of the original owner. I ultimately concluded the oil was leaking past the head gasket where it flows into the head on the pass side of the block near cyl #2. I was certain enough to pull the head a couple of weeks ago to replace the headgasket along with some other head-off tasks. Head was fine; it cleaned up perfectly with only 0.005" removed. Block looked perfect too,; no erosion around jacket ports etc. There was more gunk under the cam cover than I expected but it cleaned up nicely in the machine shop's "dishwasher".

Fast-forward to the start-up tonight. It ran very poorly as I likely wetted the new plugs with a combination of multiple 10-sec cranks with the primary lead off the distributor to fill the oil passages and a squirt of oil into each clyinder prior to installing the plugs to lube the cylinder walls. Overkill, I'm sure. So it's running on 3 cylinders with a couple of intermittent sounds coming from somewhere up top, nothing too alarming. Then I looked at the block where the leak was, smuggly expecting to see it was dry as a bone. Imagine the sinking feeling when I saw oil pouring between the head/block at a rate that renders the car undriveable. Looking through the fill cap, it appeared that there was oil in the top end but maybe not as much as there should be. Then again, I hate to run the engine above idle with cap off for obvious reasons!

So, here's the theory: I think the oil passages in the head are sufficiently restricted that the oil on it's way to the head is taking the path of least resistance. The long-standing, increasing leak may have been the result of a slow "atherosclerosis-like" reduction of the oil passage diameter. I blew plenty of cleaner and compressed air through them when cleaning up the head prior to reassembly but, with the cam out, it's impossible to force anything through the whole path. In retrospect, I remember being puzzled by the appearance of what looked like a few specks of galling on the tips of a couple of the cam lobes as well.

Tomorrow I'll pull the cam cover and cam and crank the engine over to see how much oil is coming out of the journals before pulling the head. I think there are probably plugs on the head that can be removed to access some of the oil gallery for cleaning.

So what do you all think? Am I on the right track or barking up the wrong tree?