Before putting the new one in, shine a light into any coolant journal you can see and look for obstructions. If you don't find any, put the new pump in & recheck the flow/pressure.

 

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Brew, You'll appreciate this. MANY years ago I worked in a (Ford) dealership where some of the mechanics practiced something that gives me chills to this day. When they had a freeze plug replacement job, they didn't even drain the coolant. The took the freeze plug tool, put some sealer on the rim of the new plug and drove it in directly on the old one, pushing it into the water jacket cavity without losing a drop of coolant. They would do the whole set that way, leaving a half dozen FP lodged in the water flow to obstruct the flow and continue rusting!!! I couldn't have made that up if I tried!

 

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