Thermostat removal on 2004 corolla

[friedchicken]

The haynes manual says I have to remove the drive belts and alternator just to get access to the thermostat.

Is it possible to access the thermostat without removing the drive belts and alternator?

[mikered30]

No, they must come off.

[friedchicken]

Originally Posted by mikered30

No, they must come off.

RATS!! Thanks

[invader]

Do you really have to replace the thermostat?

[friedchicken]

Originally Posted by invader

Do you really have to replace the thermostat?

I'm not replacing it. Just removing it so I can flush out the coolant completely.

Has never been changed. Its a 2004. 7 years is not good.

[invader]

Coolant is drained by opening the radiator valve and the valve behind engine's cylinder block only, as stated in service manual. Do you have the free 2004 Corolla Service Manual download? Original coolant replacement is recommended at 40000 miles. I replaced it with Amsoil 7 year/250000 mile propylene glycol coolant.

[invader]

1. DRAIN COOLANT

CAUTION:
To avoid the danger of being burned, do not remove the radiator cap while the engine and radiator are still hot, as fluid and steam can be blown out under pressure.

(a) Remove the radiator cap.
(b) Loosen the radiator and engine drain plugs, and drain the coolant.
(c) Close the drain plugs.

Torque: 9 ft-lbf for engine

2. ADD COOLANT

(a) Slowly fill the system with coolant.
HINT:

Use of improper coolants may damage engine cooling system.

Use ”Toyota Long Life Coolant” or equivalent and mix it with plain water according to the manufacturer’s directions.

Using of coolant with includes more than 50 % (freezing protection down to –35C (–31F) or 60 % (freezing protection down to –50C (–58F)) of ethylene–glycol is recommended but not more than 70 %.

NOTICE:

Do not use an alcohol type coolant or plain water alone.

The coolant should be mixed with plain water (preferably demineralized water).

Capacity: 6.5 liters (6.9 US qts, 5.7 lmp. qts)

[ToyoLuv]

Originally Posted by friedchicken

I'm not replacing it. Just removing it so I can flush out the coolant completely.

Has never been changed. Its a 2004. 7 years is not good.

No need to do all that...and if you were, I'd replace the thermostat.


Park on a hill (or ramps) with the car facing downhill. While car is on, turn heat temp knob to hottest position (this allows coolant to escape from the heater core). Shut car off, open the drain **** on the radiator. Refill with plain tap water and drive around for a minute or two until the car warms up (this allows water to circulate past thermostat). Drain and repeat again a few times but use distilled water for your final flushes. Be careful, radiator is under pressure when hot... open cap slightly with a rag to allow steam to escape before removing. After final drain, refill with good brand of antifreeze. Also remember to drain and refill overflow bottle. Check temp gauge and refill as necessary as air pockets may give the illusion that the radiator is actually full when it's not.

[friedchicken]

Originally Posted by ToyoLuv

No need to do all that...and if you were, I'd replace the thermostat.


Park on a hill (or ramps) with the car facing downhill. While car is on, turn heat temp knob to hottest position (this allows coolant to escape from the heater core). Shut car off, open the drain **** on the radiator. Refill with plain tap water and drive around for a minute or two until the car warms up (this allows water to circulate past thermostat). Drain and repeat again a few times but use distilled water for your final flushes. Be careful, radiator is under pressure when hot... open cap slightly with a rag to allow steam to escape before removing. After final drain, refill with good brand of antifreeze. Also remember to drain and refill overflow bottle. Check temp gauge and refill as necessary as air pockets may give the illusion that the radiator is actually full when it's not.

I ignored the thermostat and just did the drain and fill. I made a mess when I unscrewed the radiator plug.

Question though... how do you drain the reservoir? It looks like its one whole piece of the radiator. Do I have to siphon it out with a hand help pump? The opening looks impossible to physically stick a tube through it.

[ToyoLuv]

Originally Posted by friedchicken

I ignored the thermostat and just did the drain and fill. I made a mess when I unscrewed the radiator plug.

Question though... how do you drain the reservoir? It looks like its one whole piece of the radiator. Do I have to siphon it out with a hand help pump? The opening looks impossible to physically stick a tube through it.

There's a hose which runs from radiator fill neck down to the bottom of the reservoir. Just pull the hose from the top and let it hang low or pull it at the bottom of the reservoir. Open the reservoir so it drains out fast.

[invader]

I also drained the reservoir by the bottom hose... Did you also drain the engine block with the valve in the back?

[friedchicken]

Originally Posted by invader

I also drained the reservoir by the bottom hose... Did you also drain the engine block with the valve in the back?

I couldn't find that valve. I was busy looking for it on the front of the block. So its in the rear? Exactly where is it?

I already did the drain from the rad then filled it up with the OEM coolant. Will problems come about in the future?

On the next interval I will definitely drain it out from there. And of course of the rad drain plug too.

[mikered30]

It is located towards the back of the engine block. There is a spout and a 10mm nut.

[ToyoLuv]

Originally Posted by friedchicken

I couldn't find that valve. I was busy looking for it on the front of the block. So its in the rear? Exactly where is it?

I already did the drain from the rad then filled it up with the OEM coolant. Will problems come about in the future?

On the next interval I will definitely drain it out from there. And of course of the rad drain plug too.

You'll be fine.

[mr1114]

I'm getting ready to do a coolant change on mine soon. 130k miles. Should I also replace the thermostat? What is the factory temperature rating? its not giving me any problems and it seems they are not prone to failure as in other vehicles I've owned.