Well i finished the job of welding my coolant fittings and everything is good, fired right up. But since then, i have a hard time getting the coolant system bled properly.

I didn't drive the car much but i swear i drove it once to work and everything was fine. (20 minutes ride) The clip was still up on the overflow tank and since the level didn't move, i just decided to close the clip. This morning, i opened up the tank, put a very little amount of what i had left of my mixture and went to work. Now the coolant starts to overflow. Really like the coolant just expands and reaches a too high point in the tank and then it overflows (no clue where though).

At first i thought maybe i didn't thighten the cap strong enough and indeed it took at least half a turn but on my way back, same thing.

It doesn't overheat, 84deg C very stable but it still overflows when getting hot. Seems like i still have an air bubble stuck somewhere or i don't know what but my coolant just keep expanding when getting hot.

Please help, any clue anyone? Just ordered a new cap but doubt it will solve my problem.

 

Did you use a vacuum coolant tool?

These tools are cheap and really easy to use. IMO the only way to fill the system.

 

your issue is the reason it is recommended that idle stay at 2500k while re-filling so as to better pressurize the system. i'm guessing you simply added coolant until you reached what you thought was an acceptable level. then you added some. hence the overflow out the breather portion of the cap ( assuming that's where it's coming from ) it's a very common occurrence after re-filling coolant as in a rad replacement.

let it do what it do. it will equalize itself and that ( ostensibly ) is what the breather cap is for. look for drying coolant on the expansion tank, and take the car out for some long(er) drives. check again, the cap,.. and close the clip. i suspect it will normalize on its own. GL.

 

the level ended uo being at the min line when it cooled down so i will try it that way and hope it settles, at least, having it at min means i have a little room for the coolant to expand without dropping out.

i have used the vacuum tool and it still does it.

 

The cap do go bad.

 

I just finished my engine drop/fitting pinning, run the clip up for a few cycles with full interior heat on and higher engine rpms.(~3k), finding a slight incline with rear-end sitting higher and elevated rev's helps too...self bleeds in no time, super easy, non-issue.... will be doing the same again when I install my CSF rads..
Cheers,

 

exactly. it's disconcerting as **** to have coolant spewing out the cap until one learns that protocol