My thermostat is malfunctioning. I want to change it. My questions is do i need to drain the coolant in order to change the thermostat or its removal(old one) and installation of the new one?

Thank you

PS. Haynes repair manual says that they drain the coolant...

Engine ATW 1.8T 2000 manual

 

It wouldn't hurt would it...Actually it would if the coolant is hot/warm

 

Drain it. Red drain plug is on the driver's side of the radiator.

 

The only way you wouldn't have to drain it is if you could hold your car upside down while changing it so the coolant doesn't flow out of the hole.

Just flush it, it's good for your car anyways.

 

no need to drain just replace it and bleed the system when your done

 

how do i bleed the system?

 

let the car warm up with the radiator cap off.

 

I remember having to take the lower radiator hose off of the waterpump to change the thermostat... Am I remembering wrong or will this not drain the fluid anyways?

 

sure, if i have to remove the lower radiator hose in order to change the thermostat, its clear that a drain is needed.


PS. i didnt get under the car yet. Today its -20 below...tomorrow with a 1-2C it will be perfect

 

nope, if you leave the reservoir cap on and have the thermostat facing upwards, only some fluid will leak out. when you go put the new one back in, have someone unscrew the reservoir cap while you're pushing down on the thermostat. i put mine in with the reservoir cap on and it was hard as a **** lol