95' LHS 3.5L , Overheating troubles!

95 lhs 3.5L 175,000 miles..... Overheating trouble. Changed the thermostat and water pump as the pump was leaking. Change the timing belt and tensioner while I was in there. Notice air leak on coolant tank where brass neck molds into the plastic so I changed the tank. New coolant added. Car started right up. Temperature gauge still going full hot but it does fluctuate as the thermostat opens. Gauge needle seems a little erratic during the rise. I am not getting any leaks or steam escaping from anywhere. I am going to change the the coolant temperature sensor as this is relatively inexpensive. I am wondering if the radiator could be partially plugged also. Any ideas would be appreciated. Running out of ideas as I am slowly eliminating everything.

Did you bleed the air from the cooling system? Air can get trapped in the T-Stat housing as it's the highest part of the cooling system and will air lock it. There is a bleeder valve on the T-Stat housing that needs to be opened when you refill the cooling system to purge the air out. Fill the coolant tank to a level that is higher than the housing and leave the cap off, open the bleeder and close it back up when coolant starts to run out, then refill and close the cap on the coolant tank. Start the vehicle and let it warm up with the heater running (Temp control all the way up) when you start feeling pressure on the upper radiator hose open the bleeder valve and release any air that may have accumulated, after a few minutes repeat the process, do that a few more times until everytine you open the bleeder nothing comes out but coolant. Let the engine warm to the point when the radiator fan kicks on and observe the temp gauge. It should be mid scale or slightly higher and slowly fall as the radiator cools. Keep an eye on the coolant tank level for the next few days and top off if needed and you should be fine.

Thank you for your quick reply. Yes air was in the cooling system as you pointed out. I removed the air as you stated and so far I have not had any troubles. I'm sure the wife will let me know if it doesn't work. LOL

Thanks again..............Scott

AWP9521,

Your response was very, very helpful. I was just struggling to understand my LHS this evening when I ran across your post. I believe you've hit upon my problem.

Thanks again for sharing your experience.

Roger

Over heating!!!! everything else seems to be working properly I had this problem before and followed these instructions before from a previous post http://www.automotiveforums.com/vbulletin/t334487.html
and changed the thermostat again..

I had my sons change out the fan switch to the radiator fans and that solved the overheating problem on my '95 LHS. Hope this helps!
~ FormerTarheel.