Engine cooling thermostat

I HAVE A 1994 OLDS LSS 88 WITH A PROBLEM OF AN HOLLOWED OUT THERMOSTAT. DID NOT KNOW ABOUT IT TILL I HAVE SOME EXTENSIVE WORK DONE. MY MECHANIC IS AFRAID TO REPLACE IT. HE IS NOT SURE WHAT OTHER PROBLEMS THAT MAY COME UP. SO FAR I HAVE HAD MY UPPER AND LOWER RADIATOR HOSES REPLACED. NEW RADIATOR. REPLACED EGR VALVE, SPARK PLUG WIRES, SPARK PLUGS. OIL AND FUEL FILTERS REPLACED, AND ALL FLUIDS REPLACED. WHAT OTHER ISSUES DEALING WITH THE THERMOSTAT MAY COME UP. SUCH AS THE WATER PUMP, ETC… WHAT AM I POSSIBLY LOOKING AT??

What is a “hollowed out” thermostat? Why is the mechanic afraid to replace it?

I don’t understand this at all.

Do you mean there is no thermostat in the housing?

I too am unfamiliar with the term “hollowed out thermostat”.

If the cooling system and the engine are functioning properly, nobody should be afraid to replace a missing or “hollowed out” (whatever that is) thermostat. And the cooling system and engine can be checked out in various ways including a cooling system pressure test and a combustion chamber leakdown test.

What, exactly, is(are) the problem(s) that instigated all this work to be done?

With respect, please turn off your caps lock. All capital letters is hard to read.

Go you mean the effectively removed the thermostat? Maybe leaving the shell? If so I would guess they were having problems with it over heating, which hopefully you fixed with the new radiator. Without a working thermostat your car is going to run cold almost all the time and that will mean lower mileage and more wear on the engine as well as a little less power.

 I know I am a pest about it, but ALL CAPS are difficult to read.  Using standard case and paragraph spacing makes messages much easier to read.  Making them easier to read means more people will read it and you are more likely to get a good answer.