Coolant cap 'pop' + white smoke...

[Medic-one]

So I've put the car in service mode to get to the engine today, have taken a dozen pictures and I've a few questions now.... 🤪

I've numbered my questions to make it easier to answer 😁

I'm gonna start with the coolant cap, last year someone advised me to get a new one, which I did, but I send it back thinking I ordered the wrong one, and then ordered one that matched what I've got in the boot, the one where you top up the coolant.  So now I have 2 of those :

 

Though they have different 'dates' on the bit on the inside : 

  

 


1) Am I correct in saying the bottom one, with the 2-0 around the arrow is the newest one ? As in made in the 5th month of 2020, or I am reading that wrong ?

So I've now gained access to my engine and took some photo's : 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2) The pink stuff you can see a bit lower from the coolant tank, does that look like coolant ?

When I put my finger on it it was just mud, but then I guess it could be dried up ?

Like I said at the start of the topic the other day the cap in the boot came off when I turned the engine off, and there was a lot of smoke coming from the side vent, and since then there is a bit of a coolant smell next by the car.  However there's no leak onto the garage floor or anything. 
Also no more smoke from the side vent since.

Also I am right in saying if it was leaking there would be coolant visible on the hoses around it, but they look ok don't they ?

3) The blue coolant tank cap has the number 996.106. 447.04 on it, am I correct in saying that's the 'newest' version ? Though would it still be wise to replace it anyway ?

4) There's coolant in the expansion tank, but does that level seem a bit low, or is that normal ? When I checked in the level in the boot this morning it's sitting a little bit below the minimum level. I have previously overfilled it I think, because after topping it up and then checking again a few days later it was above the MAX level, though at the time my car was on the drive which is on a slope, whereas now I only check it whilst parked in my garage. 

Edited May 5, 2022 by Medic-one

[And.rs1800]

The expansion tank cap with the part number ending in 04 is the latest version.

  The expansion tank may seem low on coolant but these cars have a lot of coolant-when it gets hot it needs somewhere to go.as long as the level in the top up bit in the boot is above minimum it should be fine.

[Medic-one]

Just been for to collect something from the shops, drove there, parked up, all fine. 

Drove home, parked on drive, put car in garage and then when I turned the engine off there was like a 2 second hiss sound (like air pressure escaping), though no smoke and no visible leaking. 

What can cause that noise? I heard garages can pressure test the coolant system, would it be worth having that done? 

[gillbe]

If boot coolant level is unchanged since last top up (on the level surface) why worry?

[BBB]

My coolant is see through, yours looks "muddy".

Coolant https://imgur.com/gallery/2SrCKJu

[BBB]

Aargh imgur

[Medic-one]

Well spotted.

Wonder what could cause that... 

[BBB]

I don’t know, it looks like rust to me, from perhaps a rusty pipe in the system, but maybe the coolant is just old and needs changing?

[iborguk]

31 minutes ago, BBB said:

I don’t know, it looks like rust to me, from perhaps a rusty pipe in the system, but maybe the coolant is just old and needs changing?

@BBB Is there anything ferrous in the cooling system ? Bad mix of incompatible coolants causing that colour or degraded coolant like you said ? 

 

@Medic-one I'd vote get the coolant system flushed and start with a baseline of coolant you know is good. 

Before committing to that I'd also suggest get your coolant pipes inspected, your car is at an age where if they are original they may need replacing (like mine did). 

Edited May 6, 2022 by iborguk

[Medic-one]

6 minutes ago, iborguk said:

@BBB

@Medic-one I'd vote get the coolant system flushed and start with a baseline of coolant you know is good. 

Before committing to that I'd also suggest get your coolant pipes inspected, your car is at an age where if they are original they may need replacing (like mine did). 

How much was that job if I may ask? 

Sounds like the way forwards I guess, I don't want any coolant issues when driving to Italy by the end of next month... 

[iborguk]

31 minutes ago, Medic-one said:

How much was that job if I may ask? 

Sounds like the way forwards I guess, I don't want any coolant issues when driving to Italy by the end of next month... 

I had the cross-over and front pipes replaced as part of the purchase prep so I didn't see the bill (although I paid for it in the car's sticker price).  

Depending on whether the front subframe is dropped or not and who does it anything between £500 - £1K.

It's mostly labour. 

Yours may not need doing but if you do consider having the system flushed it may be a good time to at least check them.

Edited May 6, 2022 by iborguk

[Medic-one]

It's booked in for next week with a local indie to have everything coolant related checked. 🤞

[NutsyH]

On 4/9/2022 at 2:16 PM, Menoporsche said:

OMG, they were bad enough when looking at the wheel shields pointing at the valves. If I now have to check my coolant cap orientation, all hope is lost...

OOPS. When I fitted new centre shields I didn't line them up. I wondered why the wheels were vibrating😁

[Medic-one]

How long is the coolant system pressured for ? Is it only after driving or like constant ? 

Not driven the car for 6 days. Parked up in the garage, had a look underneath it, nothing on the floor.  Open the coolant cap in the boot, a lot of hissing sounds (but level still looking ok, in the middle between min and max) but when I pulled out of the garage there was coolant on the floor : 

 

 


And that wasn't there before I opened the cap in the boot...  Just suprised it did that after being parked up for 6 days. 

It's going in after the weekend to have the coolant system flushed etc, but does look like it's leaking from somewhere now, but only when the pressure is realised... Very odd...

[Paul P]

It’s not constantly under pressure.  A cold engine ( overnight ) won’t hiss at you when you remove the cap. 

no idea what’s causing your issue(s) but that isn’t right. 

[½cwt]

25 minutes ago, Paul P said:

It’s not constantly under pressure.  A cold engine ( overnight ) won’t hiss at you when you remove the cap. 

no idea what’s causing your issue(s) but that isn’t right. 

It could if there is actually a partial vacuum or low pressure after the coolant cools and that can then cause a leak to manifest itself as the pressure in normalised.

[gillbe]

Could have a small leak underneath, collecting on undertrays - and only on moving car out of garage it spills over edge of tray.  Have a look underneath to see where it has dripped from - there are pipe joints hidden by undertrays in line with dash and in line with back of seats 

[And.rs1800]

Any progress medic one?

[Medic-one]

28 minutes ago, And.rs1800 said:

Any progress medic one?

Dropped the car off this afternoon as it booked in for inspection tomorrow morning so hope to know more by then. 

[Medic-one]

So just had a phone call from my Indie who talked me through everything they've checked and done, but as I'm not mechanically minded (at all 😳) I didn't fully understand it all but when I pick it up tomorrow I can always ask some more questions. 

So he said they done a pressure test on it (using 'very high pressure') and that came all back normal. He said there was a little bit of coolant build up around the manifold but they couldn't find any leaks.  
They checked all the crossover pipes and they were fine, and he said they just done some work on a 911 on which they weren't fine, and you could really see the difference.

They've bled the system, gone for a testdrive and all seems to be normal. So they can't really find any issue's he said. 

When I asked about the coolant on the floor after unscrewing the cap in the boot (which then made a lot of noise) he said it's likely that I did overfill it and that some coolant then came out from the overflow pipe onto the floor when the system depressurised.  

I forgot to ask if they actually changed the coolant, which I don't think they have but then I brought it to them to have it pressure checked and I didn't actually ask for it at the time.  What do you guys reckon, should I still have the coolant changed or should I just leave it as everything appears in order.  It was last changed at the 60.000 service and I'm sitting at 68.000 now.  

Maybe it was a partial vacuum as CWT suggested in a post above. 

 

[Paul P]

The coolant looked pretty "murky" to me - I would ask them for their opinion - but it didn't look right.

Also - are they looking into the only hot when set to Hi thing?

 

[iborguk]

17 minutes ago, Medic-one said:

So just had a phone call from my Indie who talked me through everything they've checked and done, but as I'm not mechanically minded (at all 😳) I didn't fully understand it all but when I pick it up tomorrow I can always ask some more questions. 

So he said they done a pressure test on it (using 'very high pressure') and that came all back normal. He said there was a little bit of coolant build up around the manifold but they couldn't find any leaks.  
They checked all the crossover pipes and they were fine, and he said they just done some work on a 911 on which they weren't fine, and you could really see the difference.

They've bled the system, gone for a testdrive and all seems to be normal. So they can't really find any issue's he said. 

When I asked about the coolant on the floor after unscrewing the cap in the boot (which then made a lot of noise) he said it's likely that I did overfill it and that some coolant then came out from the overflow pipe onto the floor when the system depressurised.  

I forgot to ask if they actually changed the coolant, which I don't think they have but then I brought it to them to have it pressure checked and I didn't actually ask for it at the time.  What do you guys reckon, should I still have the coolant changed or should I just leave it as everything appears in order.  It was last changed at the 60.000 service and I'm sitting at 68.000 now.  

Maybe it was a partial vacuum as CWT suggested in a post above. 

 

Yes I'd want a flush and coolant change if it were mine and the coolant was that colour.

[Medic-one]

14 minutes ago, Paul P said:

The coolant looked pretty "murky" to me - I would ask them for their opinion - but it didn't look right.

Also - are they looking into the only hot when set to Hi thing?

 

I'm not sure if they looked into it again as I did mention to them when I drove the car over there on Monday that problem kind of seemed to have resolved, I was getting warm/hot air again from the vents at the higher temperatures, not just on the high setting.

I'll send them a picture of my coolant and BBB's coolant pictured above now and see if they can flush/change it.

[Medic-one]

7 minutes ago, iborguk said:

Yes I'd want a flush and coolant change if it were mine and the coolant was that colour.

Could that colour be from mixing 2 different types of coolant ? Obviously I topped it up with my coolant (Xtream G40) but I don't know what type of coolant was already in there from the previous owner.

[iborguk]

4 minutes ago, Medic-one said:

Could that colour be from mixing 2 different types of coolant ? Obviously I topped it up with my coolant (Xtream G40) but I don't know what type of coolant was already in there from the previous owner.

Honestly I don't know.

Again if it were my car I'd start with knowing I had good new coolant, at the right level after a system flush to give myself a baseline, but your car/cash , your rules.

I am also bit surprised they didn't comment on the coolant colour/murkiness.

Edited May 24, 2022 by iborguk