Hello all.

A few weeks ago I started my 1985 IROC, 305 TPI and let it run for about 15-20 minutes. All the sudden the coolent overflow tank overflowed and now the temperature gage stays pegged weither the car is running or not. The water pump is working fine. I checked the fuse box and all is well there. I'm going to change the thermostat but, any ideas why the temp gage stays pegged?

Thanks for any and all help.

Tony

 

I would replace the block temp sensor. It maybe got damaged during the overheat. Its cheap and if has never been replace, then its a good idea to do so.

 

Thanks for the info. I'll grab one today.

Tony

 

It's probably not the sender. The temp gage needles are prone to sticking once they're pegged up. If it stays up even with the ignition off, it can't possibly be anything in the wiring (it doesn't receive power until the key is turned on). You can remove the gage cover and poke the needle back down. If it jumps back up when the ignition is turned to 'run' check the lead going to the sender and make sure it's not loose and grounded.

Chances are your temp gage is done though.

Ohh and find out why it boiled over?

 

Thanks Naf,
Makes since. I will give it a try. Not sure why it boiled over. Picking up the new thermostat today. Hope it cures it.
Thanks again,

Tony

 

boiling over = overheating, overheating in 15 minutes = blown head gasket, boilover plus pegged guage within 15 minutes? do zee math

 

Let's not pull the heads just yet.

 

Just saying that if it pegged and boiled over that fast, something is seriosuly wrong

 

Naf was right on. Pulled gage housing and sure enough niddle was stuck. Put new thermostat and all is well. Did not think it was heads as there were not any of the typical signs.

Thanks for all your guys help and have a great new year.