1994 850 Turbo wagon oil leaks

[chax]

1994 850 turbo w/159k miles: looks like oil might be leaking out of the seam between the upper and lower block, on the back of the engine, and from between the oil pan and lower block, AND maybe through 4 or 5 of the oil pan bolts (I believe the oil pan leak began a couple years ago, when I jacked up the engine by the oil pan to change the front engine mount). The biggest problem is that the oil blows back onto the CC, and burns off; it even goes as far back as the muffler! I decided to try some RTV sealant along these seams: it helped, but there was still some oil leaking from AT LEAST the aforementioned oil pan bolts, so I unthreaded them, smeared them with some RTV, then reinstalled them. I’ll let them dry overnight, and see how that does.
1) Is a leak between the halves of the block common? How involved is resealing them? Is engine removal necessary?
2) How does oil manage to leak at the oil pan/lower block juncture? I understand that the oil might slosh up that high, but how does it manage to get THROUGH the seal? Does it become THAT bad?
As always, thanks in advance for your input.

[Ozark Lee]

To your first question, it never happens unless a rod happens to bust through the crankcase there. The sump pan leaks are more common but it is usually after a poor job of resealing the pan after the sump O rings get changed. If you do determine that the leak is at the sump then go ahead and change the sump O rings while you are at it, they will need to be changed eventually.

The sump pan is sealed with an anaerobic chemical gasket. Some people try to use RTV but it doesn't last. The stuff that works is the official Volvo pink stuff.

A much more common leak on the rear of the block is from the turbo oil line gasket and O ring.

...Lee

[chax]

Thanks, Lee. What's weird is that after having smeared a bunch of RTV sealant around the suspected leaking points, it looks like it's actually been leaking more oil!
I still have a complete tube of the Reinzosil sealant I bought when I was considering doing the pan a year or so ago.
Upon closer scrutiny, it looks like at least some of the oil might be coming from the front of the intake cam. This is surprising because I replaced both front cam seals 3 years ago. There might also be some oil leaking in the area around the front of the crank; again, surprising, since I changed out all these seals, too, when the cam seals were changed. In any case, I pulled it into the garage today, put it on jack stands, and am close to having the pan out. I'll be removing the crank pulley to see what's what behind there, too. Probably be a few days: I'll update when something gets done.