HOW TO FILL A DRY COOLING SYSTEM WITH NO AIR LOCKS

Hi Folks

Getting ready to break in a fresh 340. I have to fill the cooling system, and in the past I have experienced the odd air lock in other engines. What is the best procedure to fill it with 50/50 and be able to crank it to 2000 RPM for 20 minutes immediately after starting? Looking for a procedure that will guarantee a smooth break in with out an air lock causing any cooling problems. I have a high flow water pump and a high flow 180* Robert Shaw thermostat.

Please be specific........Rad cap on or off? Fill the rad, or leave it a little low? etc.

Thanks FABO