ejector valve???

Hi just a quickie , whilst having a spare hour , as you do I found myself underneath the hood, having a tinker with my cooling system due to having an ongoing slight overheating problem under load, decided to remove and check the 3 way valve thingy which comes from the top of rad and top near thermo,
one of the pipes breaks off!!!!
as where i am will take a while to get a replacement, i decided to open up the valve to see how it works, and seems to me it just connects the three together basically ,
so as a temp measure , I made up a three way joint from 10 mm gas pipe fittings,
is this likely to work untill I get a replacement, or does the valve have a secret function i did not spot???
Wade

what engine and vehicle if tdi it just connects the 3 pipes together so your fix will be okay,tdi over heating is usually the rad core feel radiator all over with engine off when hot should be hot all over if not needs replacing.rad will feel cooler towards bottom ,but usually faulty will only be hot on top hose side extremely common