Best way is to leave the rad cap off and run it till the thermostat opens up, and then squeeze all your hoses,even your heater hoses, this will help get rid of any air bubbles. This works best if you have a funnel that can go on the top of your rad, which helps minimize spilling, but if not just watch the level. Also to be honest you dont need to wait overnight for the rtv. Its recommended but I've never done it and no body else in the shop does. Well good luck.
Thanks, should I add any coolant to the radiator first to get some coolant into the upper radiator hose or just wait until it appears all the air is out and then add coolant as needed to the radiator to bring the level up to about an inch or so from the top of the radiator cap opening and then fill the overflow bottle up to near the hot level? Also, should I run the heater while I'm running the truck waiting for the thermostat to open?
Just add coolant. Run the heater on the hottest and the defroster on. It should take a few warm up and cool down cycles to get all the air out. If you think you still have bubbles there are some more tricks, but yeah just fill the radiator as it goes down, the excess will go into the reservoir. You'll find you don't need to worry too much about filling the reservoir up till you are close to done.
if you need to you can park uphill which will assist in getting the air out. Also after all that is done and you drive it for a week or so check it weekly until the level stops going down. I think it took my truck 2 weeks of checking it to fully get rid of the air after replacing my radiator.
Thanks. I didn't lose much coolant when I changed out the thermostat which was good. So far no apparent leaks and the after two heat/cool cycles the amount of coolant being sucked out of the overflow bottle is getting smaller.
I'll keep some coolant with me as I drive around the next week or so and add as necessary.