Silk

After a regular visual check of the coolant level I noticed that the bleeder valve is stuck in the 'up' position.

To my understanding, if the metal clip is set in the upward vertical position it will open the valve by lifting up the black center protrusion, I suppose this protrusion is internally connected to open an overpressure valve. You open it typically to bleed the coolant circuit after i.e. maintenance works is done. When the metal clip is flipped down the black protrusion in the center should go back down. So the bleeder valve is closed. Is this correct?

In my case it stays up whatever position I set the metal clip. I can force the black center protrusion down by applying a downforce. But when I remove the downforce it returns resiliently back in the up position.

What does this mean? Do I need to replace the bleeder valve cap. Or is there something wrong internally in the expansion reservoir that needs to be replaced.

Can I drive the car with the valve in the open position?

Ahsai

Check again in the mornng when the engine is cold. The valve stem should be down. There's a spring inside that pushes the stem down. When the coolant gets hot, the pressure build up will push the stem up. Once the coolant cools down, the stem should go back down.

In case yours not behaving that way, you will heed to replace at least that valve but my reco will be to replace the whole tank.

Silk

Thx ... The clip was up again when I checked now. I return it back to closed position and the stem went down. Seems to work as it should.

Now I realise that I have switched it down already several times before. Is it normal that it opens so regularly?

DBJoe996

You are not getting the function of the valve operation. When your engine is cold, the valve stem is down. When your engine is warmed up, each and every time, the valve stem goes up. This is normal operation. The wire clip is there so you can manually hold the valve open to remove air from the system if needed. Of course you can drive around with the valve held open by the wire clip, since once the engine is warmed up that would be its position anyway....up.

Silk

The engine was dropped during a maintenance 4000km/2months ago. Most probably I forgot to switch the clip down after a couple of rides. Allthough I checked coolant level at that time.

Last week I had to top off 0.5L of coolant till max level. This was also after I ran the heating on max during an hour drive. Most probably there were some air bubbles left in the heating part of the coolant circuit which got removed then.

Otherwise I do not see an explanation for the amount of coolant lost, no other then that the car spitted it out at a time I drove it hard?

Oil looks perfectly fine. Dipstick is clean. Amber coloured oil and feels very greasy when rubbed between fingers. Just the regular traces of cold-humid-weather pale-yellow-condens-drab in the very top of the oil filler pipe. Also checked coolant, it is crystal clear rosé!

DBJoe996

I would say that you are correct on each count. Not unusual after having the engine dropped, coolant system drained and refilled to have to add a little bit of coolant after several runs. Just keep an eye on the coolant level, but you should be okay now.

Silk

Thx for the quick feedback!

fpb111

If you fill to MAX when the engine is cold you will have to add every time the engine cycles through hot to cold.
The tank is commonly called an "Expansion" tank as one of it's functions is to give the coolant a place to expand when hot without leaving the car.
IE: on the ground.
Your blue filler cap part number should end with .04 to be the latest updated iteration.
The cap has a fluid bleeder to keep the tank pressure constant. If you over fill it coolant will be vented.

Silk

Mine is a blue cap with part-nr ending on .00
So this could also be the cause of coolant loss.
Will order a newer version to replace it.

Turboslut

Need some help guys.

My coolant is currently at the min level after a good 40min drive home. SO...I am assuming i need to top off some coolant.

What is proper procedure? Do I carefully open that tank while hot and add coolant or wait for it to cool down and then fill to max line?

If I wanted to ensure no bubbles...do I open that relief valve with engine cold (after adding) and then drive around for a bit?

DBJoe996

Only open the cap when the engine is cooled down. Best after a night in the garage. Just add coolant, you should be okay. Make sure you have the blue cap with a part number ending in 04.

Turboslut

Do I add all the way to to the max line while cold?

808Bill

Yes, make sure you are parked on level ground. Then keep an eye on it before and after every drive for a few days. Check your oil too!
Do you have an owners manual?

AndyK

Timely thread revival! My new OEM tank was leaking, and I replaced my ancient cap with the 04 blue one. Still dripping when hot. After reading about the relief valve, I had to force mine open with the little paperclip thingy. Something tells me it wasn't going up, and pressure built up enough to spring a small leak? I assume it should go up and down smoothly, by hand. Mine seems tight/stuck - but in the open position, my tank is leak-free!

Turboslut

Thanks all!

I bought a new cap for good measure also.