Low coolant light - Coolant Bleeder Screw?

[old89lsc]

I just replaced the thermostat on my 92 Corsica with the 3.1 V6. The low coolant light is now on, despite there being plenty of coolant in the surge tank. I have run and driven the vehicle but the light is still on.

Some forum posts reference a bleeder screw, but I cannot locate one anywhere. The closest thing that I can see is the line that runs from the top of the thermostat housing to the surge tank. In my mind, that line should bleed air from the entire system on its own since it is up so high.

Do I have a bleeder screw? If so, where?

Another internet post (not necessarily corsica specific) suggested that the coolant sensor is in the surge tank and may be stuck. There is, in fact, an electrical connector on the surge tank and I would guess that it is there to indicate the level, but I don't know for sure.

By the way, the car does not run hot now that I have replaced the thermostat. I just have this low coolant light on.

Help, please?

[jsgold]

The low coolant sensor is in your RADIATOR, not the tank. It probably has a large air bubble in it. My 91 had a screw for this near the hose where it connects to engine, but a 93 may not have one. I don't think your radiator has a cap either so that makes it rougher to do. Might try sqeezing the hose to get air moving out.

[old89lsc]

Originally Posted by jsgold

The low coolant sensor is in your RADIATOR, not the tank. It probably has a large air bubble in it. My 91 had a screw for this near the hose where it connects to engine, but a 93 may not have one. I don't think your radiator has a cap either so that makes it rougher to do. Might try sqeezing the hose to get air moving out.

You are correct in that there is no radiator cap. I have tried squeezing the upper radiator hose without any positive effect. I also tried jacking up the passenger side of the car a bit to help promote air in the radiator to exit from the discharge tube back to the surge tank. Again, the light is still on.

Since the low coolant sensor is in the radiator, what is the sensor in the surge tank for?

The screw near the hose where it connects to the engine?
Sorry for the dumb question, but which hose would that be? There is a metal discharge tube that comes from the water pump and runs in front of the engine. I followed that around to where it goes under the air intake, but up to that point there is no bleed screw on it. I don't know, but
I am wondering if for 92 that GM decided to eliminate the bleed screw in favor of the discharge line on the thermostart housing that goes to the surge tank.

I can't believe how hard this is for me.

[old89lsc]

My general conclusions about the cooling system of the 1992 Corsica with a 3.1 V6 are the following:

There are no bleeder screws in the cooling system, however, the thermostat housing has a discharge line on top of it to allow for the engine to bleed the air to the surge tank through normal operation.

There is a level sensor in the surge tank. While my low coolant light came on with several re-starts and a more than reasonable amount of operating time and squeezing of the upper coolant hose, disconnecting the sensor and re-connecting it caused the low coolant light to go out. The sensor is attached from underneath the surge tank.

My temperature gauge on the dash routinely ran to the 3/4 point before replacing my thermostat. After installing a 180 degree thermostat from Autozone, the temperature gauge stays right around 1/2.

[TonyaD]

I have a 1995 Chevy Corsica after adding coolant it an sometimes take awhile for the light to go out. I keep a watch on the temp and check levels with in a week or two the light goes out.