I have had every reason under the sun by the engine re builder as to why my engine leaks oil at the intermediate section he just want take responsibility for his bad sealing work.

The latest is it must have a blocked pcv system. Could that cause a fully reconditioned engine new pistons rings and all to leek in two spots in the intermediate section. Straight after being installed in car with less than 1km on it. This has cost me twice in taking the engine out and putting it back in with the mechanic, and now the shop that reconditioned the engine that has it back to get resealed wants to blame me for the oil leek by claiming a blocked pcv caused it. My mechanic is pissed off with the reco shop and told me they wont hand over the engine unless i pay them more money. They are just chasing for reasons to blame everyone except themselves.
The strange thing is the recondition shop does not have the PCV box as its at my mechanics.
The reasons i have had so far is bad sealer in the kit which i supplied my fault.
Oil to thin use a heavier oil.
Oil pump making to much pressure.
Oil cooler thermostat faulty.
Now the latest is the PCV blocked.