I too am having large seal leakage from my 84 244. Mine is most noticable from the front camshaft. Engine crankcase must always be under vacumm. Easy test at idle that I learned on brickboard is to loosen the oil filler cap while engine is idling. It should stay in place if engine crankcase is under vacumm and will dance if engine is under positive pressure. Mine was dancing. I located what I think is the flame trap just below the intake manifold. The owner's manual in glove box had a better picture than the Volvo Service manual. The trap had gunk in it but was not blocked. The trap has two hoses which connect it to the intake system. Small hose on block side of throttle, large hose on air filter side of throttle. The small hose had cracked and split where it connected to the flame trap. I belvieve it was not pulling vacumm at idle like it was supposed to. I cleaned the trap and put a new hose on and oil filler cap stopped dancing. I am now in the drip dry phase. I do plan to replace the seals in the front of the engine when I do the timing belt. I am hoping the rear seal has not been damaged by the excessive crankcase pressure, but time will tell.