1.5 JB OVERHEATING

Hi all, just a few obvious things I should point out. I'm running all stock parts including radiator, water pump etc

This all started a couple of days ago when I got a pretty severe leak from a slit in a hose from my water pump to a metal pipe, that's what vwheritage call it anyway I'm not too sure where it goes (to the block I suspect) anyway I lost all coolant and my car overheated covering my whole engine bay in coolant which is very rusty and concerned me! 

I did some research on top of that and found out the previous owner had put pink g12 coolant in the thing, which isn't as anticorrosive as g11 which the car would have come with, so I thought I'd use some of that after completely flushing the system! 

Fast forward today after flushing the system with water completely until nothing but clear water ran from the lower hose at the bottom of my radiator and the hole in my water pump.

 However after putting the g11 coolant in and fitting this new hose, my little golfie is running hotter than she should be while smelling the engine getting hot, then flying back down to normal running temp within a few minutes, what a nightmare 

Sorry for the essay haha, any ideas or help I'd really appreciate as I need my car for work, I know it's a not an ideal situation the car was running beautifully before all of this nonsense! 

Thanks all