Water pump prime?
I just replaced the gasket and thermostat and wonder if i need prime the water pump to or just fill the system back up with
coolant? its 89 f250 with 351w.
I would just fill it back up and fill the reservoir to the cold level. There may be air working it's way out so check your coolant level after the engine has heated up and cooled down. Make sure you have heat coming out of the HVAC system. No heat is a sign of low coolant and/or air in the system.
I added the coolant back in. Ran it and drove it around a couple times and added coolant each time because it was low. It is starting to get annoying. It should be full now right? There is no visible leaks that i can see.