[Aredubjay]

Originally posted by Mr. Pockets


By cavitate, do you mean just get air bubbles in the pump? If so, I don't see how that would be a problem. After all, wouldn't you think air bubbles going through the system are not only possible, but likely, after an oil change?

Cavitation, remember, is not just the existance of cavities (bubbles) in a fluid. It's actually caused by a fluid flowing over a solid body so fast that it drops in pressure and changes to a gas.

I don't see how this could be caused by the oil draining out. The oil pump, if I understant correctly, is driven directly by the engine. Loss of engine oil would not cause the pump to increase in speed. And if it did, how fast would the sucker have to spin to cause 10W-30 to change to a gas? I think at that point you'd be looking at so many problems, the small cavitation effect your pump was showing would be the least of your worries.

But then, what the hell do I know?

Unless I'm terribly wrong here (and it's very well likely), our cars use what's known as a spur gear pump. Here's a little lesson on how cavitation can harm such things:

http://www.nitronic.com/research/plo.html