Excessive crankcase pressure?

[ktbtrucking]

First two pictures are cm570, when you actually can see a light between head and front gear housing. So it is easy tell you have a leak from cam seals. It leaks a bit from front gear cover though. There 2.3 mil mies on this engine. Low blowby from tube.

3 and for are cm870 with 1.3mil miles and it started leaking oil a lot last 2k miles like your story.
Removed exhaust flex pipe to see back side of an engine because had large leak from outside "clutch housing" - so assume now the source of it is cam covers. Cleaned it .Run a truck for a while and it looked like it comes from cam covers.
Also had a leak originated (pic3) above oil cooler housing. Mean oil was going down on the cooler from above. It was not looking like oil cooler gasket.
Lastly pic 4 there is a lot of oil above air compressor next to fuel coolant plate ( or ECM coolant plate ) Removed both ecm and coolant plate and found nothing.

So Rawze once said to me that my head is done. Did some research and I believe you might have similar issue.
The oil leak i have have developed fairly quickly and sometimes truck runs like there in no oil in it ( Mean runs noisy.
Blowby fairly visible and when it sits running for the night I have an oil stain under the tube.(sometimes as big as tennis ball sometimes as basketball )

What I have learned from Rawze videos and website seems like when the head is worn out it vibrates a lot a you have an oil leak all over the engine.
Also poped up the rocker cover and looked for anything and found nothing.

Because I resued old gasket I believe it did not seal as strong as new one so had some leaks around cover but thightened it more and more.
Which makes me to a conclusion that there is a lot of crankcase pressure that goes up through oil drip channel.
Finally when I just covered the rocker cover without tightening it down at all had oil leaks around it all over - basicly like exhaust gasses going through cover.
Spend a lot of time reading and learning on worn out engine so would like just to share it with others.
If you have similar symptoms just stop driving and inframe it.