Not to jump in and hijack this thread, but I've battled high temp issues as well. Not to the point of boiling over, but checking with an IR temp gun, the head reads 220-235 and I shut it down. I've had the cover off and checked the impeller as well as the nylon drive gear. I'd like to take it a step further and SEE the flow for myself. If I remove the large hose from the radiator and cap off the radiator, would I be able to see the flow that way? The large hose to the head is very hot, and the lower hose from radiator to water pump is quite cool. I mean c'mon, the radiator can not be that efficient.