Just replaced my Rad in a 4.0 .. best way to burp air from system.

 

Open system you have?

 

As Roler said. Do you have an open system? If so leave the rad cap off and start it until it gut up to normal operating temp. Add coolant when it drops. Pot the cap on and drive it. Keep any eye on the rad level for a couple of day and you will be fine.

 

Open or closed systems, either way, makes no difference......let it idle with the rad cap or bottle cap off 'til the stat opens. Closed system, keep the bottle 1/2 full while idling with bottle cap off.....open system, keep the rad full to the top while idling with the rad cap off and as stated check coolant level frequently after several heat/cool cycles when the motor is COLD. I believe a '92 is the open system and a properly functioning rad cap is critical to the open system functioning correctly. Install a new rad cap as a open system rad cap has multiple valves and sealing surfaces, all of which must function correctly.