ChaddyHu68

Hi new member,, I have a 93 WRX STI version ej20, original radiator cracked bottom left corner so I replaced with one from euro car parts, the new one had x2 u-bend copper fittings onit.. original one didn't.. I have capped them both on thinking it would work all the same as ther is nothing escaping from them etc... I've done 50/50 coolant jacked the front end up as high as the trolley jack would go, and squeezed the rad pipes numerous times over 2days of the car been on the jack with the header cap off.. oh and I put an eBay made in Japan STI new pink 1.3bar cap on,, anyway heating comes on seems the engine gets hot very quick,, only ever had the car overheat in me once but i switched it straight off.... obviously was when radiator cracked.... My issue is when engine is cold you pop header cap off and coolant pushes out. And when engine is at temp the top rad pipe bulges alot...( although it is the original pipe) and I'm get bubbling in the exspansion tank that comes and goes,, water pump and thermostat cambelt etc was all done in 2020,, also when the engine is cold I've noticed the top rad pipe feels empty,, is that normal 🤔 sorry for the long story guys,, just loving the car and don't want to drive/harm it without abit of insight. Thanks in advance