Am I worrying about nothing..
 

I've started to notice my 4.6is is using a very small amount of coolant.

When first started I get a sweet fuel smell, I can't say it smells anything like burning coolant, but anyhow worth mentioning. It lasts all of a minute and doesn't smell like it again at any point until the next cold start, the following day or whatever.

I checked my coolant expansion this evening and saw accumulated around the red thing, lots of tiny bubbles. I also felt like the coolant had a slight film to it, but I had stuck my finger in the expansion after cooking with oil earlier and I've never ever noticed that before, so I don't think that's an issue. It was more the bubbles.

Here is a pic..

http://i1197.photobucket.com/albums/...4/IMG_2472.png

So I guess what I'm asking is, does anybody else notice a sort of sweet fuel smell on cold start from their M62? And should I be worried about the little bubbles?

Obviously I need to determine the source of coolant loss, but as I say it's very minimal.

All opinions welcome :)

Whens the last time you had your system flushed? The color looks odd?

The specialist that replaced the expansion tank and some other bits changed the coolant afterwards I believe, they used red coolant, whether this is correct I don't know..

However I doubt they flushed it, in what respect does it look odd?

Coolant from BMW is blue. Aftermarket is usually green.

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I think orange is polypropylene glycol, not the right stuff for the X AFAIK. Sweet smell on cold start and bubbles not a good sign though.

Yea that coolant looks odd. Have you done the valley pan gasket?

The sweet smell literally lasts a minute, id have though if it was a bad HG it would be all the time.

Really strange as it's never overheated or done anything out of the ordinary.

Nope, I haven't done the valley pan gasket yet.

Sorry to sound dumb, but what looks wrong with the coolant? Does it look like it's just old or like it needs flushing? Or like it's mixing?

Here is a pic that catches coolant colour without shadow/poor picture and without me sticking oily finger in.

http://i1197.photobucket.com/albums/...4/IMG_2473.png

Does this still look odd?

Just buy one of these test kit and know for sure if you have a blown head gasket.

https://www.amazon.com/Block-Tester-...ustomerReviews

You may smell the sweet smell when the engine first starts because coolant has seeped into the combustion chamber overnight, but once the engine has started and burned the coolant away, the pressure in the cylinder is greater than the pressure in the cooling system so coolant is no longer entering into the cylinder, but exhaust gas is leaking into the coolant system that it why you have bubbles in the system/.;

If you do have a head gasket problem fix it right away or you could be ruining the converters with that mixture of coolant and exhaust gas, or just sell the X.

Thanks, I will buy one of those and see how I get on.

It's just really strange as the expansion tank behaves the same as my E60, it sprays water in from the small pipe and when revved it sprays in and bubbles the coolant up just from spraying hard I assume but other than that there is no bubbling. Like I say my E60 expansion tank does the same and hasn't used a drop in 60k.

It was just weird that there was tiny bubbles accumulated on the red stick thing.

I'm not sure either if the exhaust is supposed to smell like burning coolant or a sweet fuel sort of smell, as it definitely doesn't smell like coolant burning, as I've smelt that before, but I'm not sure if the smell is different when it comes from the tail pipe.

The coolant loss is very mild too, if I wasn't OCD I doubt I'd noticed for a long long time.

But hey, I'll do the test and hopefully get an answer.

Thanks for your response.

Little update to this, we had the coolant cap off this evening and we're trying to investigate these small bubbles, the car will bubble when revved but there is zero bubbles no matter how hard you rev if I put my finger over the little pipe on the top of the expansion, that I assume comes from the water pump. It's almost like the bubbles are just created by the coolant stream coming from that small tube spraying/splashing into the coolant.

I'd be worried MUCH MORE about the color/product used than the bubbles IN the coolant system.
the fluid is rushing around the vehicle, creating friction and heat... bubbles are inevitable.