"Dave Packham" > wrote in
:

> Pretty sure the new radiator came with one but ill check. Would that
> be cause of the water getting to hot? Or is it that the cap is loosing
> pressure and allowing it to overflow?



Yes, that's my thinking. It might be something else, but it's the cheapest,
simplest and most obvious thing to try first and you should to it
immediately, not tomorrow or the next day or the day after that.

If cap replacement does not fix the trouble, then you should suspect the
head gasket.



> Is the water temp always in the
> boiling range, but just being contained?


No, it's only /sometimes/ in the boiling range. Theoretically, it's always
supposed to be at 194F, the rating of the thermostat.

The combustion chamber runs at about 2,100F, but coolant flow and radiator
function are supposed to be such that the coolant itself does not get hot
enough to actually boil. The pressure imparted by the action of the rad cap
is supposed to retart boiling by holding the system to about 13-15 lbs.

Modern rad caps don't even hold pressure at all /until/ the fluid begins to
boil, at which point pressure builds rapidly and the cap seals, quelling
the boiling.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/