hi, apologies if this is a noob question.

2004 sti

was just checking fluid levels this morning on the car, opened up the header tank (car is stone cold) and there is fluid in there but looks a little low, i know the car has a tank near the passenger headlight but previous owner replaced this with an aftermarket APS one which is metal and i cant see the level of this, is this just an overflow tank?

also what coolant should be going in? pretty sure it is red coolant and is it just a case of topping up from the header tank?

 

be careful when adding coolant mate, you cant mix red and blue as it congeals, you need to know whats already in it, if in doubt drain the system and re fill with either, i usually do a 50/50 mix (water/coolant) but others will say differant, the header tank needs to be full, the overflow tank needs to be aroud 3/4 full,. hope this helps,.
steve

 

thanks for the advice, i will double check with garage tomorrow what they put in it last.

regarding the overflow tank, it does not look to be 3/4 full, it looks pretty empty? whereas the header tank just looks a little low? i have done some searching on here and some people saying their overflow tanks are empty and its normal??

 

The overflow tank is just that when the car is warm it can flow into the overfolow bottle but when the car cools the small pipe in the top of the overflow sucks it back in to the system, So it is usually empty or very close to empty, Regarding topping it up of the header tank just make sure you use the correct coolant and fill it up to the lid.

 

cheers mate just what i thought, thanks for the quick responses

 

See, this was my point exactly on another similar thread and I was told I was risking HG failure (been driving 25 years and it`s never happened). I can`t see the logic in keeping the expansion tank topped up. Surely the more room in it for coolant to expand / overflow into, the better Like I`ve said, I`ve always done the same and won`t be changing.

 

I should say its better to be close to empty than fully empty just make sure the pipe is pushed right down to the bottom with a bit of coolant when cold and i got told this from my mapper a few years back as he spotted the pipe was only half way into the tank and reccomended getting a longer pipe rather than filling up the tank,

 

Fill the bottle 3/4 full and it will expell whats not needed

 

When you have done a coolant change yes but other wise why carry the eatra weight

As long as the pipe is submerged when it is cold there is already enough in the system

 

the manual advises to keep the overflow tank filled to the cold/hot lines.....as to which i do