Megane head gasket - johnny
Mayonnaise inside filler cap on 1.4 Renault E7J engine at 35,000 miles (its my dads car, so I haven't seen the extent) . Are these engines prone to head gasket failure, or is it short journey syndrome?
Megane head gasket - Toad, of Toad Hall.
At this time of year I'd bet my left nad that this is simply short run syndrome.

I changed the oil in a friends car this weekend. Even after a long motorway blast to get to me there was mayo in the rocker cover.


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These are my own opinions, and not necessarily those of all Toads.
Megane head gasket - Dynamic Dave
Are these engines prone to head gasket failure, or is it
short journey syndrome?


Has your Dad only used it for short journeys? If so, then yes, the latter. Take it for an Italian Tune and see if the mayonnaise disappears.
Megane head gasket - NormanB
Johnny

Agree to the above suggestions but also be suspicious of your thermostat unless you can prove otherwise.

NormanB