RE: cooling system

[Mike Wattam <101714.1343@domain.elided>]

Hi Richard

I think we have it.  It certainly looks like after-boil to me.  

After the high speed run, the latent heat in the engine 
suddenly cannot get away because you now have a low 
tickover speed and virtually NO water pump flow.  Coupled 
to this, because you are stationary no natural airflow over 
the engine.  All this time, the engine is still working fairly 
hard and producing lots of heat because it is 'fighting' the 
torque convertor.

First thing clearly, is to whip the lever into neutral as
 soon as you stop.  It would help also if you could manage 
to slow over a mile or two, so the engine has a chance 
of losing some of that heat.

Then look at the water pump, which means stripping out
the intake manifold to get to the pump top cover.  The 
stated clearance from cover to impellor is supposed to 
be 0.010 to 0.030", your mission is to drive down that 
clearance to the minimum 0.010" so the impellor is a bit 
more effective at tickover speed.

This is about all I can suggest, other than fitting one of 
Glenn Merrell's fan cowls which are copies of the original 
Triumph parts and are designed to pull more air through 
the radiator stationary and at low engine/road speeds.

Mike Wattam
Triumph Stag Register