[Supras] After 240000 miles I have a BHG

[JAMES]

  I have been reading about BHG's for years now. When I got my 89T it had 150000 miles on it.
 I have had to add coolant the last few days and yesterday after driving it about 10 miles I smelled
 coolant. I stopped and checked the reservoir and it was a little past the full mark. But I could hear
 the radiator gurgling and the coolant was bubbling in the reservoir. The temp was normal. I drove back home
 and the coolant level light would blink. When I got home steam was coming out of the reservoir and the
 level was low. The hose that goes from the radiator to the reservoir was so hot that you could not touch
 it. It did not look like it had blowed the coolant out. The temp gauge never went past the norm. 
   In the past few years I have replaced the water pump and the radiator. I have called today and got prices
 on having it fixed. This is the prices I got. Labor : $500.00,  Valve grind gasket kit: $295.00+tax
 Labor for a machine shop to replace the valve seals, grind the valves and surface the head :$250.00.
  Do you think I have a BHG? Does this sound like a good price? Thanks for any suggestions.