Chevy ZZ350

[Catmando]

Well the purple junk is back together and it still dose the same thing. Had the heads milled and checked for cracks and all is good there. Still pushing to much coolant out the over flow. Any ideas anyone

[michigan maniac]

More backround?? Radiator plugged? What water pump you using? Forward or reverse rotation ?  Does it boil over with the radiator cap off?  I would use block checker and see if the is combustion gasses entering the coolant,

[Catmando]

Radiator good. Not sure how to tell what waterpump I have

[michigan maniac]

Get one of these !! Can save you a headache

[MR NASTY]

My guess would be a cracked cylinder too