07 1.2 Mayonnaise on inside of oil cap - Galad
Daughter is looking to buy a 2007 Corsa D 1.2 petrol with 13k on the clock from a Vauxhall dealer. I lifted the oil cap and it's thick with 'mayonnaise'. When I pointed this out to the salesman as potentially an indication of a blown overhead gasket he just dismissed it as 'oil residue'. Am I right to steer her well clear of this car?
07 1.2 Mayonnaise on inside of oil cap - bell boy
they do do this
it does need an oil and filter change though and a good run to clear the water build up out of it
obviously check the radiator expansion bottle to confirm the headgasket hasnt gone
next time the salesman might clean the rocker filler cap and the bit underneath ;-) before the next customer sees it (i sometimes do if i remember)
07 1.2 Mayonnaise on inside of oil cap - topbloke
perfectly normal for these cars, moisture forms on the plastic cap mixes with the oil causeing mayo, Regards TB
07 1.2 Mayonnaise on inside of oil cap - Victorbox
Our Corsa C has done it from new. Needs a metal oil cap, not a plastic one to cook the moisture off the inside for the short cool journeys my wife does. That was until my 18 year old passed her test. Plenty of long blasts by her and no more mayonnaise!
07 1.2 Mayonnaise on inside of oil cap - Simon
Yep I too can confirm that it is a feature of this 1.2 engine Vauxhall engine, rather than a sign of inherent problems.
07 1.2 Mayonnaise on inside of oil cap - bathtub tom
I advised my daughter NOT to buy a car that had mayonaise so thick it formed a solid plug in the oil filler.

I know the car had only done two mile trips, but that didn't mean it wasn't (sorry double negative) hiding a head gasket problem.
07 1.2 Mayonnaise on inside of oil cap - boggles
My daughter's Corsa 1.2 used to always have emulsion on the oil cap. Seems worse in winter, even though she does a 15 mile trip usually. Even with correct oil, coolant and good thermostat, I suspect the engine does not get hot enough at the cambox area to evaporate off any watery deposits. The 1.2 Agila she has now, is similarly affected to a lesser extent.
I just wash the cap off with white spirit, whenever the oil is checked.
07 1.2 Mayonnaise on inside of oil cap - Lud
Mayonnaise isn't especially harmful although the water in it may cause a bit of unimportant rust. As long as it disappears after a couple of hundred miles of brisk road it's nothing to worry about.
07 1.2 Mayonnaise on inside of oil cap - Rattle
When I sold my Fiesta the scouser who bought it off me found mayo and started mouthing of about head gaskets etc until I explained I had used it for short journeys. I asked him to check the smoke smell it, I also asked him to check the header I think he believed me that the HG was fine.

When looking at cars it is all too easy to assume the first sign of mayo or steam is the HG I've done it before but I always thought its best forget about the car before spending £1K'S only to find out it was the HG.

I had a worry when I got my Corsa 1.2 because it was spurting out a lot of water at the back, so I went on the motorway came back and its been fine since, it was just codensation in the exhaust caused by the stupid amount of short journeys I do.
07 1.2 Mayonnaise on inside of oil cap - bell boy
i lost a sale on a corsa yesterday due to a luddite thinking the headgasket had gone
i tried to explain but to be honest once these people think you are trying to sell them a failed headgasket case car you might as well go boil your own head
i suppose the fact the mot was done last week and the hc reading was 7 was also immaterial as i couldnt be bothered showing him the printout
07 1.2 Mayonnaise on inside of oil cap - Rattle
A leaking head HG could pass an MOT though if crack is minor I assume as the emessions might still be ok. Bellboy do you do compression tests on all the cars you sell? If you do these checks it might be worth advertising the fact. One of the garages I dealt with seemed very honest they said they would happily do a compression check in front of me etc but I think the cars were genuine anyway they just didn't have any cars I fancied but I would visit them again if I need a new car.

I did walk away from a streaming Focus once but the steam was really excessive and the temperature seemed way to high, when i looked at others since I realised I was probably right to avoid it I still wonder if I did let a good car slip though because of phantom HG problems.
07 1.2 Mayonnaise on inside of oil cap - bell boy
i dont need to
i do an mot type emmisions test and code read all cars these days
the emmisions tester wont lie if the hc is 7 then you know the engine on the hg side is tickety boo
problem arises when garages havent got a clue and just fumble in the dark for an answer to an awckward question
knowledge is king always was, if i dont know i find out, the internet still helps me in my job which is why i often help others
07 1.2 Mayonnaise on inside of oil cap - Rattle
I am not sure what HC7 means but I assume it tests for antifreeze and oil in the exhaust fumes?

Never understood what any of the readouts on the emissions meant.

And yes the internet is wonderful, learnt so much from sites like this
07 1.2 Mayonnaise on inside of oil cap - Lud
a luddite thinking the headgasket had gone

er... yer what bb? ... not one of mine my dear fellow I do assure you...