Been working on an1988 XR4. Doing a few extra things on the cooling.I have had problems with it over heating. After replacing the water pump the pressure is still low (3 to 8 psi). Thinking of a way to flushing from the top down. Can this be done by adapting a water hose to top where the water pressure gage connects to the engine and pushing water into the system? Removing the foot, could this help remove any blockage?