Hell I think that is the way we all were taught years ago. I can remember lining them up in a coffee can,filling it with oil above the top of them,then using a Phillips screw driver to pump the plunger till the air was out. Then trying to start the engine and wonder why it didn't have compression?
What IQ said...
In the 80s I pumped them up in a can of oil (yes... actually a can...lol).
Now I assemble the engine with them dry, set preload carefully, pre-oil it, and have no problems.
