Thermostat?

Question

when changing a thermostat do you have to drain the coolant? And if so do you just unclamp the bottom horse of the radiator? thanks

Answer 1

You can either unclamp a hose that is lower then where the thermostat is or let the fluid drain from the little spout in the bottom of the radiator. Make sure you dispose of the fluid properly (NOT ON YOUR LAWN OR IN THE SEWER DRAIN) cause it kills dogs.

Answer 2

yes, you have to drain the coolant. yes unclamping and disconecting the lower radiator hose is usually the easiest. There is usually some left in the engine so when you take the thermostat housing off it'll make a mess, at least it does when I do it, so make sure you can get it cleaned up as quickly as possible so any animals don't get into it and before it can soak into the ground. Antifreeze is deadly if ingested.

Answer 3

Some cars have a petcock on the bottom of the radiator that will allow you to drain some fluid out. On others, you have to loosen the bottom hose and drain some out.

It is not necessary to drain it all out, normally, just a gallon or two will lower the level enough to replace the thermostat. Put a bucket underneath and then you can reuse the fluid. If the fluid is over 2 years old, then it would be a good time to replace it with fresh coolant.

good luck.

Answer 4

You should change your coolant when changing the thermostat. It could be one of the reasons the thermostat went bad anyway. It is recommended that you change your coolant every 1-2 yrs unless it is high mileage coolant. After a period of time the coolant can become highly acidic and eat up engine parts causing engine failure..... and yes dispose of it properly it will kill any animals. You can drain it through the petcock on the bottom of the radiator or remove the lower hose when the engine is cool.

Answer 5

yes you do have to drain the coolant.
instead of unclamping the hose, on the bottom inside portion of the radiator there is a small petcock that you turn to drain the radiator.
drain it into a pan so you can put it back in. if you pull the hose you'll probably lose a lot.
car overheating? i assume so, or else why would you want to replace the thermostat.

Answer 6

You don't have to drain it. You'll get some fluid when you loosen the top radiator hose, but you'll only lose a portion of it. Make sure the car is cooled off proprerly before you touch anyhting. If you do need to remove coolant there shoud be a petcock on the raiator you can open, but it may be plugged. If so you may have to remove the bottom hose.

Answer 7

Usually there's a drain on the bottom of the radiator. You can just drain it about half way, but it's cheaper in the long run to drain it all and put in new when you're done. When you're done, make sure you let it idle with the cap off 'till you see the coolant flowing, then fill it and fill to the line in the overflow tank, then put the cap on and turn off the motor.

Answer 8

assuming its on the top and not the bottom of the motor ,
drain just enough to lower the level under
where the thermstat is.
best way to drain is unscrew the value on the botton of the radiator... its looks like a T top on a screw.. with a hole in the middle.. twist it til fluid comes out..
make sure you clean both sides of the cup where the new therm goes.. use a gasket with just enough paste to hole it in place.. too much and its a mess to get off next time

Answer 9

I wouldn't recommend doing that. Take your radiator cap off first then locate your radiator `pet-cock' near the bottom of the radiator and turn it counterclockwise[with a pan under it]
Drain a couple of qts out of it then tighten it back up.
replace your thermostat [read directions] and refilll the radiator.

Answer 10

If your car is completely cooled down and not under pressure, you can just switch it out like that. There is no need to have remove any radiator fluid to change your thermostat since your thermostat is at the highest point in the system. Just don't change the thermostat while your cooling system is under pressure. Its a good idea to change your rad fluid as a preventative maintenance thing though.