[Healeys] Thermostat?

[ggilliam at usol.com]

On Friday I drove my BN4 to the "Back to the Bricks" car festival in
Flint,MI, about a twenty five mile trip, the last half mile quite congested
, with all manner of classic, collector, muscle or specialty cars filling
the entire downtown area. Thousands of them! 

On the way home that evening, coolant gushed out, in large quantities,
overheated, requiring my first ever use of Hagerty road assistance. 

 Saturday morning I refilled the radiator, over 1 gal required to fill it.
Car started immediately, but I didn't see the usual coolant circulation
that I have noticed before. I removed the thermostat, a bit of rusty film
on it, but normal looking. Went for a 10 or so mile drive, all appeared
normal, temp stayed low (~160). 

 The thermostat is the usual automotive type, maybe 10 yrs old. The
question is, is the much more expensive ($80 or 43) sleeved type in the
Moss catalog really that much better? 

 Comments....suggestions? 

 Gordy 

 Longbridge BN4