looking to do a coolant flush on my 90 civic dx 1.5 for the first time that i've owned the car. whats the easiest way to do so? i didnt get a chance to look yet, but i'm assuming there is a drain at the bottom of the rad? what about the plastic coolant bottle?

thanks in advance!

 

The most thorough way would be to open up the thermostat housing, remove the thermostat, and remove the radiator cap. With the thermostat housing open, run water from a water hose in the top of the rad. It will flow through the entire engine and run out of the open housing, flushing any debris or old coolant with it. After that you can open the radiator drain and remove the water and replace with coolant. Just be sure the housing has a good seal when you reconnect it & you should be good. Hope that helps

 

drain the old coolant and get the water hose to clean out any dirt, dirty water ect. and after that put the drain plug and get one gallon of 50/50 coolant and turn on the car and leave it on til the thermostat open and to get out any air bubbles and some coolant may spill out and after that replace to radiator cap and you done

 

yea very simple... just charge an arm and a leg most places.. make sure you run your car after you fill it for 10-15 mins.. then go back after it cools down alittle bit check the radiator and add alittle if need be.. but other than that good first time thing to do for sure..

 

and i forgot to add while you have you car on turn the heater on to make the thermostat open faster