Oil (lots) in Coolant Tank

[MBLOVERMCR]

My coolant header tank looks completely full of oil!! Hope you can help!!

My C220cdi W204 (2013), with 111k miles on her, told me to top up my coolant yesterday, and today it told me to check my oil level. I've never had the oil level warning before so it was concerning.

I've gone to fill up the coolant and noticed the tank is seemingly full of oil. I've never experienced anything like this before and don't know what to do. Is it a big problem? Surely if oil is in the coolant system, water is in the engine? And a big bang is imminent?

I recently had the manifold changed my Mercedes - approx. 2 months ago. Could this be a factor?

Will this kill the car if I keep driving with it for a while?

 

[Trickythemerc]

Needs urgent attention or it could end in big engine failure. Head gasket could be the culprit, get it looked at ASAP

 

[Petrol Pete]

Coolant mixed in the sump with the oil . Oil mixed with the coolant within the engine.

If it were an F1 car the driver would not be asked to 'Box Box' , he would be told 'STOP THE CAR !'

Don't start it up until it is fixed

 

[StMarks]

Have a look at the oil.
There being that much oil in the coolant suggests a very serious failure with some component, however oil in the coolant is the (very slightly)less concerning direction.
Check to see if there is coolant in the oil.
Look to see if the oil has taken on a creamy consistency (emulsified) or if there is any evidence of coolant whatsoever in the oil.
Either way, this needs sorting asap, & I personally wouldn't even consider driving it until the problem was sorted.
If it isn't a head gasket or cylinder head failure, it could be the heat exchanger (oil cooler).
Good luck, and please let us know the outcome.

 

[MBLOVERMCR]

Thanks for the quick replies. I'm panicking obviously but the F1 analogy brought a laugh! So, thanks for that!

Luckily (for now) there is no evidence of coolant in the engine.

Could it be linked to the work I had done recently? I had the manifold replaced six weeks ago, whilst stripping the car down, do you think it's possible a gasket was damaged or not replaced? Because as you say, the volume of oil in the tank suggests a serious failure. Mercedes had to get a fabricator out to remove bolts and rethread the block - surely the mechanic removed the head to facilitate this?

 

[StMarks]

Luckily (for now) there is no evidence of coolant in the engine.

Surprising, but you are extremely fortunate if that is the case mate.

Could it be linked to the work I had done recently? I had the manifold replaced six weeks ago, whilst stripping the car down, do you think it's possible a gasket was damaged or not replaced? Because as you say, the volume of oil in the tank suggests a serious failure. Mercedes had to get a fabricator out to remove bolts and rethread the block - surely the mechanic removed the head to facilitate this?

It would seem quite possible. Do you have an itemised bill, because if so I would expect that would tell you what work they did.
If (for example) it happens to be a heat exchanger failure, that would be less likely to be as a result of such work imho (unless they re-filled the system without corrosion inhibitor aka antifreeze).

 

[zipdip]

Well there might be a slight possibility that the removal of bolts might have damaged the head gasket,but very hard to prove,as others have said get the car looked at the oil in water is the best outcome if a head gasket has gone water in the oil is not ,do not drive it.

 

[StMarks]

Well there might be a slight possibility that the removal of bolts might have damaged the head gasket,

? Perhaps more probable that a crack or breach in the water jacket was created when:

,,, had to get a fabricator out to remove bolts and rethread the block

But (as I understood it) what MBLOVERMCR was proposing, was that the cylinder head may have been removed for this procedure. If so, then this issue may well be as a result of a failure resulting from that.??

 

[MBLOVERMCR]

Many many years ago I was a mechanic at Ford. In all my years I never saw a coolant tank with oil like that. I regularly saw a bit of coolant contamination in the engine block but never the other way round. So I’m really miffed by this.

I can’t find the sales invoice, it’ll be around somewhere, but below is page 2 of the quotation - there are a few gaskets and seals included.

 

[MBLOVERMCR]

And back in the day…

If any of the mechanics were unfortunate, or too rough-handed, and the block needed rethreading; the head was always removed from the block. Never saw a re thread carried out with the head in situ.

With the lack of room in these engine bags I don’t see how it can be.

 

[StMarks]

Many many years ago I was a mechanic at Ford. In all my years I never saw a coolant tank with oil like that. I regularly saw a bit of coolant contamination in the engine block but never the other way round. So I’m really miffed by this.

FYI my (beloved) little motorbike is a model type that inevitably results in most of them ending up spending much of their lives on the racetrack. The ACU regulations stipulate that (for race use) they must be run with water only (so as to avoid contaminating the track with slippery antifreeze in the event of a crash/spillage).
Unfortunately the aluminium heat exchanger fitted to the Daytona engine seems particularly susceptible to corrosion when the coolant system does not contain corrosion inhibitor. Consequently they seem prone to failing catastrophically, and the highly pressurised oil is blasted into the coolant system.
I'm NOT saying this is necessarily the case with your engine, but it may be some comfort to know that there can be breaches where the oil goes out in large volumes relative to coolant entering.

I can’t find the sales invoice, it’ll be around somewhere, but below is page 2 of the quotation - there are a few gaskets and seals included.

That being a quote, presumably did not reflect the actual bill (as you indicated that the fabrication work was unforeseen, and therefore extra).
Quite obviously there is no head gasket in that ^ list of components, nor the labour involved for such a task.
The disparity between the quote and the invoice may be enlightening.?

 

[MBLOVERMCR]

There we’re a few activities included in the original quote that I didn’t progress e.g parking sensor fault. So there is a bit of difference between quote and cost.

It was £460 to diagnose the original fault and a further £1,100 to fix. It was supposed to be £460 to diagnose and circa £600 for the manifold. The cost went up when they stripped the bolt(s) - they generously allowed me to pay for a machinist to fix that.

It’s a big relief that fluid appears to be traveling only one way. But I can’t drive it so that’s a bother, and it takes weeks to get an appointment usually.

I’ll call the garage tomorrow and I’ll pop an update on when I can.

Thanks for your help! I’ve posted a few times on this forum and I’m always stunned by;
A) How knowledgeable people are and,
B) How quickly people get in touch.
I’ve had a minor meltdown since finding the oil, so the contributions are greatly appreciated!
Cheers.

 

[alexanderfoti]

The oil to water heat exchanger has failed. Its likely not related to the recent work carried out. Oil system is under higher pressure than the cooling system, so oil enters the cooling system.

 

[MBLOVERMCR]

The oil to water heat exchanger has failed. Its likely not related to the recent work carried out. Oil system is under higher pressure than the cooling system, so oil enters the cooling system.

Thanks. Is that a big job to fix? Any ideas on labour/parts? I’m just weighing up whether it might be time for a new car.

 

[alexanderfoti]

Thanks. Is that a big job to fix? Any ideas on labour/parts? I’m just weighing up whether it might be time for a new car.

Not a massive job. Less than 900 all Inc