water locking and rear radiator???

[werty]

I have the 4.3l in my toyota and its not flowing water to the radiator all the time. Symptoms are surges every few seconds when its hot not a constant flow. I can watch the hoses on the outlet shrink and expand when it surges. The highest hose has a vent, I can open to let air out. The radiator is about 2'' higher than the outlet hose.
Do you guys put a higher gpm pump on when using a rear radiator? Or am I missing something?

[WHITE_TRASH]

Water can't compress and the water pump flows at a constant rate.  So if there is a surge it much be caused by air compressing in the system somewhere....  When I had a rear radiator in my truck I tried everything I could think of to get all the air out and ended up parking on a very steep hill and pulling the heater hoses off the heater core then putting a hose adapter I made in one of them and bleeding the air out of the other.  Once I found that trick I never had any issues again.  The only thing I changed from stock was to use a factory water pump pulley that was a bit smaller than what was on there.