Hi folks, have a '97 petrol endura 1.3 engine in my fiesta. Noticed recently there was quite a bit of white gunk inside the oil filler cap. Engine has done 80,400. Haven't topped up the expansion tank for some months, not needed to. Did I ought to get some raditor/head sealant in readyness? Car otherwise runs ok at the mo, although I noticed heater/engine doesn't get warm of late (temp. gauge doesn't enter normal area), although it has been pretty cold weatherwise, of course. Hope someone can advise.

White gunk that looks like mayonnaise on the oil cap is a sure sign oil and water are mixing and a new head gasket is required sooner rather than later.

White gunk that looks like mayonnaise on the oil cap is a sure sign oil and water are mixing and a new head gasket is required sooner rather than later.

Yikes....... ok, thanks for that, any idea what a reasonable cost for replacement would be?

Just a quick note of caution my 98 fiesta had the same white gunk on filler cap at 24,000 miles . However clean the cap and check to see if it happens again or if water in expansion tank goes down. my car went on to 100,000 miles and never did gasket or head change somtimes the breather in the oil cap gets bloked and causes this. hope this helps.

Ok, thanks for that info, I will certainly keep a close check on the coolant level from now on.

white gunk can also appear if the car is used for short journeys all the time.

you get the gunk from condensation in the engine too as well.

HGF usually has a misfire with it,check your dipstick too.

Thanks for the comment, Mintalkin. However, I should have stated that it's normally used on long runs. Just don't remember the gunk being there on previous occasions when I've topped the oil up.