Not sure if oil in coolant or not

[Elon Musk]

Hi all,

Last week, when my bonnet was open on my 2000 K11, I glanced at the coolant tank, and it looked as if there was a very thin white line of something sitting on top of the coolant in the front corner (it's parked downhill). I bounced the car and it instantly disappeared. I then drove 60 miles, left it overnight, and the next morning the thin white line wasn't there. So I put it out of my mind.

But yesterday, before I set off for work, the car had been sat overnight, I noticed it again - it's only slight, but I'm sure it's never been there. So I bounced the car, and whatever it was quickly dispersed into the coolant. It had a milky-ish colour to it.

When I take the cap off the top of the radiator, I can't say I see what looks like oily deposits, but there is a very thin layer of something, like a slight sprinkling of dust or something. I've never seen this on this car. It's always been crystal clear.

Does anybody have any inkling what this could be? My worst fear is a head gasket on its way out. I've had one blow on a previous Rover 400 and it basically wrote the car off, and left me having to quickly look for and buy another car.

There is no mayonaise under the oil cap, nor does it appear water is getting into the oil - no bubbles or mayo on the dipstick at all. Could this simply be gunk in the coolant system? I have no idea how old the coolant is, nor how old the radiator is (I'm assuming 23 years old).

It's only a slight thing at the moment, but I'm very in tune with this car, and would have previously noticed this. So it's definitely a recent development.

 

[Twincam-Alex]

Do you know when was the coolant was last changed?
I've found coolant looses it's colour and becomes murky looking after a long time.
May be worth flushing the system and putting fresh coolant in if you haven't already done so.

 

[adrianblack]

Hi all,

Last week, when my bonnet was open on my 2000 K11, I glanced at the coolant tank, and it looked as if there was a very thin white line of something sitting on top of the coolant in the front corner (it's parked downhill). I bounced the car and it instantly disappeared. I then drove 60 miles, left it overnight, and the next morning the thin white line wasn't there. So I put it out of my mind.

But yesterday, before I set off for work, the car had been sat overnight, I noticed it again - it's only slight, but I'm sure it's never been there. So I bounced the car, and whatever it was quickly dispersed into the coolant. It had a milky-ish colour to it.

When I take the cap off the top of the radiator, I can't say I see what looks like oily deposits, but there is a very thin layer of something, like a slight sprinkling of dust or something. I've never seen this on this car. It's always been crystal clear.

Does anybody have any inkling what this could be? My worst fear is a head gasket on its way out. I've had one blow on a previous Rover 400 and it basically wrote the car off, and left me having to quickly look for and buy another car.

There is no mayonaise under the oil cap, nor does it appear water is getting into the oil - no bubbles or mayo on the dipstick at all. Could this simply be gunk in the coolant system? I have no idea how old the coolant is, nor how old the radiator is (I'm assuming 23 years old).

It's only a slight thing at the moment, but I'm very in tune with this car, and would have previously noticed this. So it's definitely a recent development.

Head gasket on the way out mate or slight crack in head. White stuff is emulsified oil. Oil that has been whipped into the water then when it stands for a while the scum comes to the top of expansion bottle until next time it gets agitated by the water pump again.

 

[Elon Musk]

Twincam-Alex, I've no idea. For all I know it might be the original coolant.

adrianblack, I'm leaning more towards it being the beginnings of head gasket failure too. The thing is, despite being 23 years old, it's only got 36k miles on it. For a k11 it woud surprise me if a head gasket fails with such low mileage. My other K11 did 125k before I sold it, and it was the most reliable car I've ever owned, as were the other 3 in my family.

I've booked it in for a coolant flush on Thursday, so will speak with the mechanic and perhaps ask for the head gasket to be changed anyway, just to be sure. Fingers crossed it's not a cracked head.

 

[adrianblack]

Twincam-Alex, I've no idea. For all I know it might be the original coolant.

adrianblack, I'm leaning more towards it being the beginnings of head gasket failure too. The thing is, despite being 23 years old, it's only got 36k miles on it. For a k11 it woud surprise me if a head gasket fails with such low mileage. My other K11 did 125k before I sold it, and it was the most reliable car I've ever owned, as were the other 3 in my family.

I've booked it in for a coolant flush on Thursday, so will speak with the mechanic and perhaps ask for the head gasket to be changed anyway, just to be sure. Fingers crossed it's not a cracked head.

Sometimes it's more age than mileage mate. The metal rings around the cylinders and bolt holes, oil /water galleries etc in the head gasket corrode away and aluminium head with steel bolts just need a bit of coolant around them to make a nice battery which causes all sorts. Triumphs used to have major problems with the recardo engine until saab bought it and put stainless bolts in. Just a bit of useless information for you lol. P.S. sometimes coolant leaks into engine show up on exhaust gas emissions test.

 

[Elon Musk]

Cheers mate. In hindsight, I did find it odd that I needed to top-up the coolant with 200ml about 3 months ago, but couldn't, and cannot find any leaks. Hopefully I'll get it sorted end of this week.

 

[Elon Musk]

An update for anybody that feels like shedding light.

I rang the garage, told them oil in coolant, and asked for head gasket to be checked and changed as well as coolant flush. Receptionist said she'd talk to mechanic and ring me back.

She rang back saying the mechanic claimed it's a common problem with these cars, and it's most likely the timing chain, but they can't change it as they don't have the specific tool - then wished me luck

That doesn't make sense to me. How could a timing chain cause oil to get into the coolant? That's an entirely new one on me.

 

[.Maarten]

It cant. Also no special tools required for the timing chain.

 

[adrianblack]

Ey up. You mentioned having to top up water. Is oil clean ? Do you have slight misfire or hesitation now and again? If you do have slight misfire it points to water being drawn into combustion chamber which again is probably head gasket sealing rings corroded. Get to a little independent tyre place that do mot's and slip them a few quid to do exhaust gas test. It usually shows up water in gases but give it a bit of a run first to get condensation out of exhaust. Good luck

 

[adrianblack]

P.S. one of your spark plugs will also have a different colour tip if it's getting the tiniest amount of water in the cylinder. My m8 had exactly same thing with his punto so I had head skimmed and fitted new gasket. Spot on.

 

[Elon Musk]

There is no hesitation or misfire at all, nor can I see even the tiniest evidence of water in the oil, so feel 99% confident it's only oil getting into coolant. At least I think it's oil. It's mayo coloured, and dissovles into the coolant when I bounce the car, and there's a bit more of it 3 weeks after first noticing.

I don't have spark plug sockets, but it's booked in to a very reputable garage on 6th June for a diagnostics. Fingers crossed it's just corrosion on sealing rings, and the head won't need skimming.

 

[Micra Paul]

Using garages/mechanics to investigate hypothetical faults & its remedy costs need to be equally established & compared with a 23 year old vehicle of little replacement economic value?

Perhaps it may be worthwhile to control costs by getting firm fixed price quotes for any & all proposed diagnostic/servicing /repair works & or investigations to avoid costs spiralling thermal run away.

good luck