i will usually use a small amount of silicon on the gasket and were the o-ring seats in the pump just in case. Also, when you go to put the truck back together after checking the pump and are done setting the timing belt up, fire it up with just the timing belt and balance shaft belts on to see if everything aligned properly. this way if it the balance shafts are not timed correctly you can immediately fix it. make sure thou that nothing will get caught in the timing belt like the spark plug wires and such. the balance shaft belts will make a vibration that you wont miss if they are not 99.99% correct. I do it this way just to save myself the trouble of removing everything again.

Oh and if that's an eBay dnj pump, get rid of it. i bought one and it would do the same thing because it was cast wrong. go with one from you local parts store, they are not expensive at all.

good luck.