Quote Originally Posted by dr. d View Post
it shouldn't be difficult to design fillers/caps that offer good sealing.
so i wonder, is this non-sealing cap by design, poor choice of cap, or simple poor workmanship?
mostly erroneous desgn and measurement of the radiator throat, the radiator cap fitment on top of the radiator is sometimes out-of-round preventing proper sealing. to make sure of the fit, measure the depth of the throat sealing ring and compare with the radiator pressre seal protrusion.