siglincasey

My stock cap was 16 and the one the store said it called for was 13lbs. Is that all right? Or do I need to get the 16lbs?

RTorrez1

It should be a 16lbs. But since you didn't put any info on what vehicle you have I can't be 100% sure.

siglincasey

It's a 95 xj. 4.0 H.O. 4x4

black2000xj

my 99 is 16lbs if that helps

siglincasey

Thanks. I know it has some thing to do with letting water in the reservoir, but that's all I know.

djb383

The 13 and 16 both let coolant into/out of the bottle in a "open" type cooling system (non-pressurized bottle). One will release pressure at 13 psi, one will release at 16 psi. The 16 lb cap raises the coolant boiling point 9*F higher than the 13 lb cap.

siglincasey

So, will that keep the block cooler?

Sparkys92XJ

^^^X2

From what I've understood that changing your radiator cap changes boiling point like before stated. And that affects people at different altitudes. Because the boiling point changes at different altitudes. So having a 16 lb. cap will just increase boiling point and delay your coolant going into your overflow tank

djb383

No......the 16 lb cap just raises the boiling point 9*F above a 13 lb cap. If coolant boils, bad things will happen.