Subaru Problems? Ask a Mechanic for Answers ASAP
If you are leaking oil out the port, then you must have cut the valve guide seals when you installed them. Did you use the plastic sleeve over the valve tip when you installed the seals?
When you had the springs off, did any of the valves fell loose in the guides?
If you have to be manifold off and the engine not running, do you see oil leaking out the port?
Do you have good vacuum to the pcv system?