About a week ago I seem to have resparked some debate on the subject of the AMS water pump pulley and it's fitment. The topic spun out of control here: [ http://www.twinturbo.net/nissan/300zx/forums/general/view/2324255/The-AMS-H20-pulley-has-offset-problems-and-runs-the-belt-at.html ] Full disclosure: I along with several other vendors sell a competing product. I do not manufacture, produce or otherwise "make" it. AMS (or their hangers on) have claimed that thousands of their pulley have been sold. Last week 3 people offered to mail me their as yet uninstalled pulleys for comparison. I accepted offers from 2. I performed these tests w. 2 of the AMS pulleys. Here are the 3 pulleys side by side:
Stock pulley:
Stock pulley belt offset @ 20mm from timing belt cover:
HI Pulley:
HI pulley belt offset @ 20mm from timing belt cover:
AMS pulley:
AMS pulley belt offset @ over 22mm from timing belt cover:
As stated before, the AMS water pump pulley is offset incorrectly and causes drive belt misalignment between the water pump, crank and alternator pulleys. This will cause incorrect loads on the water pump and will with time prematurely wear the pump's bearings & seals. Additionally I placed both the AMS & HI pulleys onto a standard shipping scale. The scale was calibrated to "0" before each item was placed on it. Given the holes cut into the mating surface of the AMS product the results might surprise you. HI 4.4oz
AMS 4.8oz
Bernie Bilski berniebilski@cox.net 1995 Nissan 300ZX TwinTurbo in Cobalt Green 1997 Nissan 240SX SE in Ultra Red ZCCNV #390 ~ ECZA #368 |