Melling pump cover bolt torque

Well that's why I ran the pump on the bench till its clear before I install it on the engine, I did high and low speeds with the drill, took it all apart again, cleaned everything off again, carb cleaned the housing, dried it, reassemble with engine oil again, torqued the cap down.

Hate to say it, but your carb cleaner may have damaged or removed that coating altogether. Double check with Melling.