87 Cherokee with Renix 4.0. New heater core, new radiator, new thermostat, new thermostat housing, new water pump, new hoses (heater and radiator), converted to open system, heater valve deleted, engine flushed when the water pump was off, but the block was not drained. Basically the entire cooling system is dry, save the small amount in the block. So I am thinking that when I fill this system with new coolant, I will first fill the heater core via its lower hose until it runs out of the upper hose. Then fill the engine block via the heater output port on the thermostat housing, then slowly add coolant via the radiator filler neck with the upper radiator hose disconnected, in an effort to prevent air pockets in the radiator.

Does this sound feasible? I am trying to prevent air pockets in the entire system.

Thanks for your patience and help.

 

I use a vacuum pump connected to where the radiator cap goes. Don't even have to have the engine running to bleed all the air out. Takes less than 5 min to fill and bleed the whole system.

 

My method on the Renix? Well I start by taking the upper radiator hose off of the radiator, holding it high, and filling slowly from there until it comes out the radiator. I can then start the Jeep, let it run, "burp"/purge the air, then top off the remaining fluid.

 

Since you converted to open, any entrapped air will eventually make it out of the radiator an into the overflow bottle after a few heat/cool cycles. Just make sure you watch the level in the overflow and top off as needed.