On OM617 Turbo motor, what is the most effective way to check if the water pump is good or bad while still in the car.

The seals are good as there is no weeping.
It does not squeal so bearing are good.
My temps are good and steady under all conditions / loads at btw 79C-85C.

However, when I pinch the upper Radiator Hose then release I dont feel the "Surge" everyone talks about. Maybe it is subtle?

If the coolant in the coolant tank is "moving" then I can assume water pump is ok?


Thanks

 

Yep, that rad hose be hot *** hell when temp is about 85C. I can assume that pump is fine. I could always yank the hose and crank her over, but really not necessary at this point in time.