sciontc_mich

Okay so been thinking about a coolant change and noticed that in the service manual they're talking about a bolt on the engine that is to be loosened to help drain out the fluid. Not the two valves on the radiator.

If I don't loosen the one on the engine block, will the fluid still drain out of the radiator? I think yes, but wanted others who have done this to tell me what they found.

What is that bolt for on the engine block? I thought it was a pressure relief to drain out the fluid from the head/block, but if I do that dont I risk having to rebleed air out of the cooling system?

Thought it would be easier to not loosen that bolt and just drain the coolant out of the radiator and refill.

DeathStalker

you can do it through the purge valve/ drain plug from the radiator
take out the thermostat
run it with heat on full blast for a minute, cycles the coolant from ur heater core and hoses
drain
put thermostat back
fill
run
top off

thats so you dont have to mess with the block. but if you do idk where its on the scions but i think you remove the drivers tire and there should be a threaded freezer plug just take that out and drain. make sure the block is cold so you dont mess up the threads.

i think thats right. when i wake up later i'll see if its right.

Ace83

iTrader: (6)

i just did mine using the radiator, there will be coolant left on the block though but pretty much most of the coolant will drain just using the radiator drain ports

10gxiong

I just drained the coolant with the radiator plug. Afterwards, filled up the radiator and coolant resovoir. Once that's done, with the radiator cap off I just ran the car with the heater on until the fan turned on for about 5 or 10 minutes to burp the the system of air pockets. When i didn't notice anymore bubbling of fluid from the radiaor, i turned off the car, topped of the radiator and radiator resovoir if necessary, and put the cap back on. I don't know where the bleeder valve is either.

sciontc_mich

Thanks! to everyone that replied. i had to ask since that's what I was going to do just drain the radiator and NOT mess with the engine block. something just said not to, so i'll follow those instincts. easier to drain and fill the radiator.


one more question, how did anyone get to the lower drain valve? Did you have to remove that plastic shielding under the car to get to that valve?

Ace83

iTrader: (6)

i have not done coolant change on stock radiator, but just try to remove the radiator support on top so you will have more room for the radiator to move around.. i dont even remember how the stock radiator drain is positioned

sciontc_mich

oh didn't know you had an aftermarket radiator.

there are two valves on the driver's side of the radiator, one is for draining the radiator the other is to bleed air out of the system. I think I figured a way to get to the lower one without removing the under engine shield.

sciontc_mich

UPDATE: Well did the work but the coolant didn't come out that well until the lower drain valve **** was removed completely. The service manual is saying that the O-ring on the drain **** plug can't be reused.

Any harm in reusing it? I didn't know this at the time,anyone have any thoughts on this replacing of the o-ring everytime its removed? I just reused the old one, didn't even think about it.

sw09

well the service manual also states that you should replace the oil drain plug gasket after each oil change etc...its as long as it isnt cracked or too stretched out you'll be fine

Ace83

iTrader: (6)

it can be reused as long as its not so stretched and worn, if it needs change it would leak.. it wouldnt hurt to replace it too, you should be able to find same oring sizes in auto stores

sciontc_mich

Been checking on it for the past couple of days and yeah its leaking. So yup, its going to get fixed. Ill take a close look at the old one when I take it out to see where it was leaking out, like worn or stretched. Didn't think a coolant job was going to be this involved lol

thanks for the input.

DeathStalker

probably just the o ring. i think a pack of assorted ones is $3, stealership will probably charge you the same for just the one