I have a 92 accord lx and it appears that the thermostat is stuck closed, so im planning on replacing it myself rather than take it to the shop. I was wondering, is it necessary to drain the coolant in order to replace the thermostat? If this is the case im planning on flushing the system to clear it out and i was wondering how exactly i would do that? I've looked it up elsewhere but couldn't find clear instructions.

-thank you

 

Make sure to get some radiator flush before you replace any thing...

 

If the thermostat is stuck, it seems a safe bet that there's crud built up in the cooling system.

I normally remove the thermostat & also disconnect the upper radiator hose. That way I can use a garden hose to flush tons & tons of water through the block, and separately through the radiator.

Try (as best you can) to look inside the radiator for crusty crud build-up. If so, use some radiator-flush product to clean it out. Then rinse it till there's no trace of that stuff left in there.

Make sure your heater is set to full-hot so the heater core gets rinsed out too.