Possible Head Gasket Failure?

[andy®]

Hi all, i've been browsing the forum for a while, but i thought it was time to introduce myself.

Anyway, i went to top up my oil earlier on, and the oil cap is all milky on the underside. I'm a little worried that the head gasket may have gone, however, there doesn't seem to be any other signs of a problem. The car runs nice and smooth, doesn't seem to be losing coolant or over-heating, and is achieving a regular 400 miles per tank. Has anybody else experienced a similar problem?

My car is an 07 reg (June 2007) and has covered only 5000 miles from new, all done by myself. I know there's a possibility that serious damage could result from further driving, and Toyota recommended not to drive it at all. However i need a car for work so i'm hoping they'll be able to provide me with a courtesy car asap.

What else could cause a milky oil cap? I'm always vigilant about checking my oil, having owned a Civic Type-R as my previous car.

Regards, andrew.

[johnan]

Milky deposits can be due to the engine not being run long enough to properly warm up and evaporate any moisture "in" the engine/oil.Do you only do short runs?

A thermostat sticking open would have the same effect.

[andy®]

My journeys tend to be around 15 mins to work and back, and then a 200 mile round trip at the weekend. However, i've never experienced a similar thing happening to other cars i've owned, driving the same routine as i do in my Aygo. I'm hoping it's nothing to worry about, but it's always better to be safe than sorry.

andrew.

[T600]

Check the oil cap after your 200 mile journey (once the engine has cooled down for an hour or two). It'll probably be much better.

But keep an eye out for the other symptoms - high temp, falling or rising oil level etc just in case.

[johnan]

A 200 mile trip should be enough to heat everything up nicely!

Did you actually need to top the oil up when you noticed the milky deposit?

I check the oil weekly but so far, touch wood, the level has not moved and thus has not needed to be topped up in 10000 miles.I therefore may have the milky deposit too but as I have never had the oil filler cap off, I wouldn't know!

Makes mental note to have a look tomorrow.

If the water level is constant and the engine runs fine there is not really much else to suggest.

I expect MrT would only be interested if there was something very tangible wrong with the engine that they could identify and fix.

[andy®]

I was just checking the oil to see if it needed topping up, and at the same time i always do a general check, including under the oil cap just in case there's any signs of a problem. Mr T has said to pop in tomorrow morning, so i will keep you all updated on the outcome. I expect they'll do a quick inspection, send me on my way and tell me to keep an eye out for any change in the car's characteristics.

Thanks for everyone's help,

Andrew.

[BadBoyVTEC]

there was a post about this already. the outcome is that there was nothing to worry about as it was due to short journeys

[aygo-bloo]

there was a post about this already. the outcome is that there was nothing to worry about as it was due to short journeys

Agreed.

I picked up my brand new 'Blue' yesterday and when I got home I checked the oil filler cap. After a total of 18 miles on the clock there was a milky deposit evident.

All of my old VW Beetles used to show the same symptoms if I only did short trips and they were all air-cooled so weren't able to have head gasket problems! ;)

[andy®]

I came to the same conclusion that it was due to short journeys, and didn't bother taking it into Toyota. Instead i've clenaed up the cap, and i'll look at it in the morning as i've just got back from a 200 mile round trip. If the milky substance has returned, then it's clear that short journeys are not the cause. However, if this issue has popped up a few times on here before then i'm a little more relieved that it's not resulted in anything serious.

Thanks for all your replies, andrew.