[TR] Radiator Caps

Randall TR3driver at ca.rr.com
Sat Mar 17 10:41:01 MDT 2012


> I've know places to pressure test the 
> cooling system up
> to 15 PSI (over night).

Something that complicates this picture: The pressure is not constant
throughout the system when the engine is running.  In order to circulate the
water, the water pump has to create a pressure differential.  How big the
pressure differential is depends on several factors, including engine rpm.
Some of the racers have reported finding over 30 psi at the heater fitting
on the rear of the head (with no heater attached, of course) during
sustained high rpm operation.

> I have read that others have mentioned about short
> neck Rad. vs the 'standard' neck, but I don't know if they 
> mean the actual
> 'neck' that the cap attaches on or the 'extra' length that 
> protrudes from the
> rad that the cap attaches to?

I think sometimes they mean one thing, and sometimes the other.  My
understanding is that they changed at the same time, but I could be
mistaken.

-- Randall  


More information about the Triumphs mailing list