Fiesta 1.0 oil cap sludge - Ford Dagenham

My wifes Fiesta has got a cold.

I went to top up the oil as its below the full mark and i found this grey/green mass of cream under the cap and in the rocker cover hole there isnt any on the dipstick.

The cars details are :
Fiesta mk3 999cc L spec not LX 4 speed manuel with 55 thousand miles on the dial.

I havent told me wife as it may upset her.

Martin Winters
Fiesta 1.0 oil cap sludge - Rob E

First question: does the car do a lot of short journeys? If so, this is caused by the oil condensing as it never heats up enough and a white creamy sludge forms under the filler cap. This used to happen very frequently with my Mum's Peugeot 106 (1.5 mile round trip per day). It is not a serious issue at all and is not a fault. Just wipe it away and take the car on a long hot run to get the oil circulating. This phenomenon is a reflection of the fact that the internal combustion engine is not designed for short journeys. If the car continues to do short journeys this cream will continue to reappear.

If, however, the car does not do lots of short journeys and there has been a loss of power, it may indicate a problem with the head gasket... this is a territory I know much less about so I'll stop now!

Hope this helps,

Rob E.
Fiesta 1.0 oil cap sludge - Ford Dagenham

My wife does 10 miles a day to work and back with varying engine speeds.

The car was serviced on september the 29th would the oil need changing to compensate for this weather.

apart from a whining gearbox i don't think there is any loss of power as there is not much of that anyway i see what you mean as it would be very noticeable.

Best regards.
Martin Winters
Fiesta 1.0 oil cap sludge - Cliff Pope
I don't know this engine, but all I am familiar with have some kind of ventilation system that vents the crankcase by drawing air constantly into the inlet manifold. This should ventilate the top of the engine too, possibly via another hose connection.
Check that all this pipework is in order, not blocked, and in particular that the small vent into the inlet manifold is not blocked - they often are.
Check that the engine is running up to full temperature - an overcooled engine will be especially prone to this sludging. Check the temp gauge,and thermostat. Is the fan running all the time when it should be cutting out?
Maybe the radiator needs partly blanking.
Old BMC engines were prone to this, and the cure was to open out the restriction in the rocker cover vent pipe.
It would be better to stop the sludge if possible, because it will contain corrosive combustion product condensation which will eventually work its way into the oil.
Fiesta 1.0 oil cap sludge - Ford Dagenham
Hello thanks for the reply.

How do i go about blocking the radiator.

When the temp gauge gets to just before the red the fan comes on.

Iam due to be using her car in january to drive to brighton as my car will be serviced on that date will that mileage kill off the sludge.

Best Regards
Martin Winters
Fiesta 1.0 oil cap sludge - eMBe {P}
How old is the car? When did you last change the oil & filter? Is it losing coolant?

Use the forum search button (on the right, not the one at the top); search for a combination of terms like "oil mayo coolant sludge baileys" and you should find lots of references to this problem.
Fiesta 1.0 oil cap sludge - smokie
Had this problem regularly with our Fiesta Azura - see

However, the car has now passed to my daughter who is doing many more miles, and, touch wpood, the problem has gone away.

It used to only be a problem in the colder months.

And, as someone suggest above, make sure the breather pipe which comes from the oil filler cap is clear. When we were having the problems, the car would regularly cut out through some sort of starvation in that area, shortly after a cold start. The quick "get you going" was to remove the filler cap, start it, let it run for a few mins before replacing the cap (then clean it all out with paraffin when it got home...)
Fiesta 1.0 oil cap sludge - smokie
And anotehr thing...

I once had an oil change and the car conked out the next day. The cap had got filled with muck in about 10 miles driving, even on new oil.

That's when I discovered the inside of the rocker cover was gunked up with emulsion...also required regular cleaning
Fiesta 1.0 oil cap sludge - Spanner Jack
Have you tried fitting a hotter thermostat ?
Fiesta 1.0 oil cap sludge - Claude
Having had 7 Fiestas I can say the smaller engines are prone to this. Dont worry about it, wipe it out of the filler, change the oil at 6 month intervals if you are doing shorter journeys and I also use a flushing oil every couple of years. A run to Brighton will do it a lot of good, specially if you changed the oil immediately afterwards. It only takes 10 minutes on a Fiesta.
Fiesta 1.0 oil cap sludge - Ford Dagenham
Hello thanks for the replies.

What is a hotter thermostat and how is it fitted.

How do i remove the rocker cover and how easy is it.

Thanks very much
Martin Winters
Fiesta 1.0 oil cap sludge - Spanner Jack
Hotter Thermostat:

Most car manufacturers specify different temperature thermostats for use in the winter or summer.

ie a summer thermostat may open at 82 degrees C, a winter one at 88 degrees.

If you put a hotter one in, then your engine will run at a higher temperature, and the condensation will have a better chance at evaporating.
Check with your parts accessory shop, or main dealer to see if the option is possible on your engine...
Fiesta 1.0 oil cap sludge - smokie
I think I'm right having called it the rocker cover, I meant the bit which the oil cap goes onto. There are six or eight bolts around it's edge, unscrew then and it just lifts off. There is a gasket all the way around it, make sure this is properly aligned when you put it back as it prevents oil seeping out.

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