[Dollar Bill]

As Mike pointed out, it depends on whose leakless water pump you have installed. Mine came with these instructions:

The rear grease fitting should be lubricated every 500 hundred miles. Because the rear bushing of this pump is sealed, it is necessary to back off the pack nut when greasing. This will allow the air to escape and avoid damaging the seals. Pump grease into the rear fitting until you see it coming out between the shaft and the bushing.