What pressure are you BEC chaps using on your coolant system caps.
I have a 10lb cap and I lost some coolant on Tuesday when stuck in traffic. Temp guage was only showing 90degs.

Cheers
John

dint have a rated cap on mine, neither have i put one on this, if its an expansion tank int it "sealed" as such ??

I agree with Jon.

The air above the liquid in the expansion bottle should allow some coolant 'expansion' but the cap will have no pressure rating.

The pressure rated caps are for the older cars where coolant expansion wasn't allowed for in the design of the system.

The blade rad has a rated cap in it IIRC, not sure what pressure it is tho.

Chris

Doesn't each 1lb of pressure in the system raise the boiling point of the coolant by a degree or something like that ?.

Confused now.
Surely you have to have some pressure relief in the system? what gives in the event of worst case scenario.
I spoke to Ian at ST today and he runs with 13lb caps.

The relationship between coolant temp and pressure has always irritated me.
Am I right? water can exist in liquid form at higher than 100degs if under pressure.
and the temp guage will reflect the actual temp. of the water, say 110degs.
Release he pressure, water and steam spray everywhere and temp guage will drop to <100degs.

John, with a headache.

John youve got it right. The reverse effect is if you boil water on the top of everest, it boils at about 70deg, so dont go up there if you want a cup of tea.

From a distant memory it boyles law P1T1=P2T2. but could be wrong.

Gordon

[Edited on 9:7:04 by Mk-Ninja]

Aah, Boyles law. It all comes flooding back now.
Thanks Gordon.
Think I'll go for a higher rating cap, also will check my guage is reading correct since I was bubbling up and the guage was showing 95degs.

Cheers
John

Haha - that's boyle's law fellas, not boils law.... I think boyle's law is just about the gas phase!
Bob C