I assume you mean pulling the distributor and using a priming tool or 1/4 inch deep socket duct taped to a long extension, chucked into your portable drill, to primer the motor with oil? No harm in doing that with the engine out. The key, however, is to make sure you have the crankshaft lined up to TDC and your rotor pointing to the number one terminal on the dist. cap before you pull the dist. It helps to put a piece of tape along the side of the dist. housing and mark where the rotor is pointing before you pull it. Help when reinstalling. When you reinstall, put the rotor about 1/2 inch or so couterclockwise from where you want it to point. As you insert the dist. the curve in the splines causes the shaft to rotate as it seats. I've been told that you have primed the engine enough when you see oil coming up through the rockers. If you are going to pull a valve cover to check this, pull the passenger side valve cover so you can check that the number 1 cylinder is on its firing stroke when you pull the dist. Good luck. I always found it hard to get the dist. back in, to seat all the way. I've been told to drop it in where the rotor is pointing where it hsould, then turn over the engine by hand and the dist. well drop right in as the oil pump drive shaft rotates. Instead, I've used a flashlight to peer down the hole and see how the drive shaft is lined up, then turn it a bit with a 1/4 socket if it doesn't line up with the dist. Don't know how many times I've had the socket come off the extension doing that. it is a pia.