Hi volks,

Some radiator shops have an infrared "gun".  It measures heat radiated from
whatever it is pointed towards.  You can use this to scan the radiator for
"cold" areas.  A new radiator will be uniformly "hot" across the front
surface.  As radiators clog or become coated internally with various
materials (including the worst of all, Alumaseal), the coolant is thermally
isolated from the inner surface of the tubes.  Heat transfer from coolant to
tube to fin is impaired.  The coolant can't dump as much heat and the
temperature rises.

The heat transfer across a boundary is proportional to the temperature
difference across the boundary and also to the thermal conductivity of the
material at the boundary.  The poor conductivity of the insulating sludge or
the blockage of some of the tubes can lead to severely reduced cooling.

If you can find a shop with a "heat sensing" gun, have them profile your
radiator.  They'll usually do it for free as it points out the problems for
which they would be more than willing to sell you a solution.

IMNSHO, the WBX cooling system is marginal at best with a poor waterpump
design and location and lots of flow restriction in the rest of the system.

cheers,

pensioner