hi folks, lately have been having leaks with my expansion tank and thanksfully i managed to detect the area of the leakage so i applied an adhesive and currently no more leaks but the coolant fluids still goes down alot after a short trip like 20miles. i took it in to my autoelectrian and he discovered that my thermostat takes too long to come on and so my coolant fluid boils out and even when it shots the fans to come on it on does so in a few seconds and then it goes off. he therefore put another thermostat somewhere and the problem has been solved but the fans are too loud. Anyway can i change the original thermostat without any problems?

 

baffourg, you have to run a 195F thermostat. You can run a lower temperature thermostat, but it is going to be at the cost of lower mileage as the ECU will see the motor as not being up to temperature and it will run the motor rich until it can get it up to temp (which obviously will not occur since the thermostat is keeping it at a lower temp).

I would look at your water pump too. It is possible that the water pump is starting to go and it just isn't pumping the water around like it should, leading to your situation. Normally when a water pump starts to go, you will see a little bit of leakage around the seal for the drive pulley.

 

my autoelectrian has installed a 75/70degrees thermostat on one of the hose and i think that explains why the consumption has changed which is not a problem but the fans are loud this time around and they keep coming on and also take a while before they go off which makes me noticeable anytime i drive around cos i think people want to know why my cat is so loud. Anyway is it ok to disconnect the original thermostat without the check engine light coming on?

 

baffourg, are you talking about the thermostat (mechanical device that regulates the engine temp) or are you talking about the temperature sender that sends the temp of the engine to the ECU? These are 2 different components.

 

well, am not knowledgeable in this area so if u can throw more light on it and also what can be done.thanks

 

You have 2 pieces that are associated with engine temperature. You have a mechanical device (located below the controller for the fans, kinda centered behind the radiator where the coolant hose runs from the bottom of the radiator up to the top of the engine) that its sole purpose is to control the flow of coolant through the radiator, which then maintains the temp inside the motor. The other part is the temperature sensor. All this does is monitors the motor temp and then sends this information (electronically) to the ECU, which then can cause the ECU to turn the fans on if needed. The temperature sensor also can cause the ECU to force the engine to run rich (when the motor is not at normal running temperature of 195F (90Cish)). If you install a lower temperature thermostat (mechanical device), then the temperature sensor will tell the ECU to run the motor rich because it is not up to the proper temperature (due to the mechanical thermostat keeping the engine cooler). This will happen all the time since the motor never reaches its optimal temperature.

Is this making a little more sense?