Question on thermostat

[Don in VT]

Hi All,

My water pump is in and I am ready to install my Samco hose kit. I was intending to change out my thermostat with a NOS part # 10135627 that I bought from Butler Chevrolet.

I pulled Mark H.'s article on the defective Stant thermostats # 14068 and compared it to the old unit that I just took out of the car. I seem to have one of the defective units as it looks identical to the one that Mark identified as defective.

My new NOS unit looks like the "normal" unit that should be installed.

When I continue to compare, I see that the defective Stant 14068 has holes punched all around the wax valve. The NOS unit does not have any holes in that area but there is a rubber seal in that location where the defective unit has holes.

Question: Do I need a thermostat with the holes?

The interesting thing is that my car seemed to be running fine with respect to engine temp.

Any help here would be much appreciated.

Regards,


Don

[Marc Haibeck]

Hi Don,

The old thermostat does not have the rubber center because it has disintegrated. The thermostat probably has over 50k miles on it.

The correct bypass spring deflects .5" with 5 lbs. pressure, not .5" with 1.5 lbs. pressure.

The engine will warm more quickly if the thermostat does not leak through those holes found in the worn out unit.

Good luck with the reassembly.

[Don in VT]

Hi Mark,

Thank you for the reply as it totally answered my question. I should have caught that one myself as upon closer inspection I noticed that some of the holes has residual rubber in them. I am good to go with the NOS stat.

You saved the day again !

Best Regards,

Don in VT