Finally got all my parts in the mail and im about to start putting my baby back together when I realized that with the koyo rad I now have two spots for radiator caps. Now heres the question, how do all you aftermarket radiator guys have yours setup? Do you just use the water pump cap to fill it and use the radiator cap as an air bleed? Or do you get a different filler neck on the water pump or something of the sort?

 

^bump

 

I have an S5 motor, so the Koyo fill is the only one.

If I were you, I'd use a really high pressure cap on the waterpump fill, and a regular pressure cap on the radiator, route the line for the overflow tank to the radiator cap.

PaulC

 

your gonna have to use the same pressure caps on both since they are connected. use the one that is highest in the sytem.

 

you don't want the same pressure caps on both because then coolant will come out of both under pressure. and you only have a hose on one... one should just be a fixed cap that won't open. but a really high pressure one would work too. and run the overflow line to were the lower pressure cap is.

use the higher one. probably the water pump. so air can get better.

 

Yup like Scott said.

The one without the over flow bottle tube shoudl be a fixed cap(no spring crap)

On mine it is the one on the waterpump neck. I use this as the fill point.

The pressure cap then goes on the Rad. Like said above if you use 2 pressure caps then both will open. The one without the over flow tuibe will suck in a lot of air which isn't good.

 

where does one aqcuire a non sprung radiator cap?