Interesting.
That's been possibly the worst issue with mine.
I've been through about six idler pulleys, three H20 pumps and a radiator.
I attributed the pumps (and rad) failure to the poor design of the heater core height that traps water and turns it into system plugging rusty sludge.
...combined with the pressure on the pump shaft from the serp belt.
I still have a pinhole in my H/C that I'm not really thrilled about pulling the dash to fix.
Doesn't effect operation or pressure of system but smells a bit of coolant if heater is on. (BTW the heater SUCKS).