Today the outside temperature was 46.5 C in my region. For the first time the heat gauge of my car crossed 105 and it was quite near the red line.
The clutch fan is direct. Makes lot of noise but had always kept the car temp in between 85 to 90 C. Today despite that as stated above the heat gauge shouted up.
The radiator coolant is clear and there is no junk deposits seen in the coolant reservoir bottle. Had changed it a year back but not with the Merc recommended coolant.
The coolant reservoir bottle cap has never been changed. May be the cap is the main culprit and causing heat in the system. What cap number I should go considering the hot temperatures in my region?
Secondly if I remove the thermostat valve, will there be any reduction of heat in the engine. I had also changed the thermostat valve a year back. 75 C.
The heat gauge does come slightly down when the car is on the main highway but in city it comes near the red line with AC. Well without AC it is normal. Both the front fans are also working at their first speed.
Any advise to control the heat in the engine will be highly appreciated

 

check for any leaks and the hoses, maybe a crack in the radiator??

 

I had similar issue with the coolant temp. I'm waiting the aux. fan sensor to be replaced. I will get the JimF. coolant harness if the problem won't go away. (thermostat is new, radiator is new, fan clutch is tight and working)....

 

Battlecat you were 100% right. There was a small leak in the coolant bottle. It was on the upper small hose which goes to the coolant bottle. Secondly i have also changed the coolant bottle cap. It was very old. Now there is absulately no heating problem.

Thanking all of you for your help

 

Welcome mangg...yeah you have to check for those leaks. Air that gets in and circulates around and into the radiator = major heat issues...