I had loads of trouble with mine, firstly I would wonder why it split, if your happy that it wasn't an underlying problem like head gasket failure then you need to burp it, basically what I had to do after much research, is this
jack the car up at the front as high as you can possibly get it, fill up with coolant in the rad then put cap back on, then fill through the tank that's near your abs pump (that extra little tank with a rad cap on), then you need to get a bottle (bottom cut off)or a funnel and make it fit Into that tank nice and snug with no leaks so that basically you can fill up the funnel/bottle so that the water level is a good 6-8 inches higher than the actual tank with a few inches spare at the top of bottle/funnel for expansion and for when you squeeze the hoses, then you need to mostly fill up that bottle and run your car maybe for a good 20 minutes maybe 30 or 40 depending on how long it takes for your themostat to open, so probably 20 mins after its opened and the car should be fully burped (keep an eye on temp gauge), squeezing hoses like a madman (watch out for spinning engine components, belts and pulleys etc), in between the hose squeezing you need every 3 or 4 mins, to rev your car up and down to 2500 rpm and maybe hold it at 2500 for a few second here and there, then straight back to squeezing hoses, keep an eye on the funnel/bottle, so that the level doesn't go down to far, you can also see the bubbles coming up in there (if it's clear plastic) , if your car doesn't have another problem then this should burp it, you must get it as high as you can on the jack tho
hope this helps (hope your car has the tank by the abs pump lol )