Hello everyone I am new to the forum. I have looked around a lot trying to find a answer to how to prime the oil pump in my 91 M5. I have tried bumping the starter but I am not getting any oil pressure. I have read on the forum if you have a extra oil filter cap to drill a hole and put a nipple on it. This is my question because I have read different things in the forums. Do you pull a vacuum using the nipple like you are getting air out of the brake lines or do you pump oil into the oil filter housing. Thanks in advanced any help would be appreciated.