How do i drain coolant ? E30 318is

[mjc85]

I have a 1990 E30 318is, just wondering how do i drain the coolant system ? I have opened the bleed valve on the radiator side tank but only a litre or so of coolant came out, how do i get the other 5.5 litres of coolant out ? Can someone point me in the direction of a guide or just run me through the steps here.


Thanks
Mitch

[Jon325i]

Unfasten the coolant hose that ties into the bottom of the radiator. Its gonna be messy, but I guarantee you that a lot more coolant will come out. I don't know if the M42 has a drain plug in the engine block.....the M20s do, on the right side below the exhaust manifold. If your motor does, remove that as well and it should drain nearly every drop.

Jon

[mjc85]

Ok and how do i fill it up again once i have drained it ?

[mjc85]

Ok well i un-did the valve on the bottom of the overflow tank and let that drain then it all drained and i rocked it a bit and more came out, but i dont know from where ? Radiator ? Then i filled up the overflow to the line on the tank, but when run the car now it overheats and if i feel the radiator hose it feels like no water is flowing in or out of the radiator ? Does this mean i have air in it ? or what is wrong ? how can i fix it ?

[royalflush313]

Ok well i un-did the valve on the bottom of the overflow tank and let that drain then it all drained and i rocked it a bit and more came out, but i dont know from where ? Radiator ? Then i filled up the overflow to the line on the tank, but when run the car now it overheats and if i feel the radiator hose it feels like no water is flowing in or out of the radiator ? Does this mean i have air in it ? or what is wrong ? how can i fix it ?

did you properly bleed the system? If you just filled to the line on the tank, you do not have enough coolant in there.... you should check your coolant level.

[mjc85]

Ok how do i check the coolant level ? And how do i bleed the tank ? I have look through the car manual but i can't find it in here, i searched google without much luck either.

[royalflush313]

Ok how do i check the coolant level ? And how do i bleed the tank ? I have look through the car manual but i can't find it in here, i searched google without much luck either.

Well you said that you filled your coolant to the level right? If you can do that, you can check the coolant level. Simply do an eye-check to see that the coolant is still sitting at that line - the chances are it is not.

To bleed, drain, fill couple inches above the level line, start up the car with the heater fulll blast. You will see the rad hoses getting warm, when you feel that, slowly loosen the bleed screw, let all the air escape. Once the bubbling stops coming out, tighten up everything, turn the engine off, and do a final check on coolant level.
After a lil while of driving, it's probably a good idea to re-check the coolant level.

I'm no mechanic, so please, if someone can refine what I wrote above, it'd be nice for you and for future reference.

[2002maniac]

Actually it works best with the heater on low. The motor will warm up faster and the t-stat will open burping out the air. keep filling up the rad as it gets sucked into the motor. when you can tell it is warm. Raise the revs a bit and loosen the bleed screw(right next to the filler.) when it stats leaking out pure coolant with no bubbles you are good. Top it off to the line, cap it, and drive it. After a while loosen the bleed screw again and you should get more air out. Have fun!

[royalflush313]

Actually it works best with the heater on low. The motor will warm up faster and the t-stat will open burping out the air. keep filling up the rad as it gets sucked into the motor. when you can tell it is warm. Raise the revs a bit and loosen the bleed screw(right next to the filler.) when it stats leaking out pure coolant with no bubbles you are good. Top it off to the line, cap it, and drive it. After a while loosen the bleed screw again and you should get more air out. Have fun!

cool, I didn't know that. I always assumed that heater full blast would work heat up the fastest :?

[mjc85]

One prob, my fan speed only works on 4. 1,2,3 don't work because the switch is broken

[blunttech]

fan speed makes no difference. what you want here is the heater valve open so all the air is allowed to escape.
escape isnt the right word. so the air is allowed to be forced out of the heater core. you know what i mean

[2002maniac]

fan speed makes no difference. what you want here is the heater valve open so all the air is allowed to escape.
escape isnt the right word. so the air is allowed to be forced out of the heater core. you know what i mean

Well, fan speed does matter. If you have it on 4 it will take longer to heat up the coolant and open the t-stat. All that air blowing through the heater core transfers heat from the coolant to your interior. Doesnt matter much, but it will take forever to warm up with the heater on full blast. I know you already knew that, just thought I'd clarify.

[Henna Red]

fan speed makes no difference. what you want here is the heater valve open so all the air is allowed to escape.
escape isnt the right word. so the air is allowed to be forced out of the heater core. you know what i mean

Well, fan speed does matter. If you have it on 4 it will take longer to heat up the coolant and open the t-stat. All that air blowing through the heater core transfers heat from the coolant to your interior. Doesnt matter much, but it will take forever to warm up with the heater on full blast. I know you already knew that, just thought I'd clarify.

It really dosent matter, the heater core dosent remove enough heat to really impact how quickly the motor gets up to temperature

[Zoso]

Pictures tell a thousand words :)

http://zoso.no-ip.org/318i-thermostat.html

[damionphillips]

Could be a stuck thermostat, too. Have you replaced it?