How much antifreeze in avantis ?

First - Open the air bleed c*ck in the top of the water manifold so that all air can escape as you fill the system. When only antifreeze comes out the bleed c*ck then close it and continue filling until the expansion tank is half full or just to the seam. If you fill farther than this don't worry - the excess will just blow out the overflow when hot and running until the level equilizes to about the seam.

This has been my experience others may have differing suggestions.

Jason Ford R4478 "1963r2"

Are you talking about anti-freeze or coolant mixture (about 50/50 antifreeze / water)? (Title says "anti-freeze") Rinse off any mixture that gets out when bleedig or at any other time, too.

The owners handbook says the level in the expansion tank should be 1" from the top.

I premix 50/50 antifreeze and water, to fill the system. Ethylene glycol antifreeze is poisonous. A puddle of the stuff in the driveway can be drunk by pets or other animals; and is attractive to them because it tastes sweet, (like pumpkin pie, I'm told). An overflow tank / coolant recovery system will eliminate the hazard. It will also allow the system to purge itself of air, and make the car run a little cooler. A square tank sold by Stude suppliers and parts stores fits neatly in the right front corner of my Avanti engine compartment, without the wire hanger. No mount is needed. I use a "Stant 228" 7lb cap, from Advance Auto. I think it came with the double seal for the recovery system; or the washer from the kit worked with it. The lower pressure allows the system to "work" at normal operating temps. The level in the recovery tank goes up and down; and the stock expansion tank stays full to the brim. The higher pressure, 13lb, cap just lets the engine overheat more before the coolant boils, and the system fails. It is useful for pushing dents out of the expansion tank; and probably leaves fewer puddles, if you don't have a recovery system. Mike M.