9 replies to this topic

[Pavel]

Okay after a 5 mile drive i took off the rocker cover. The whole rocker cover on the inside is covered in mayo, with oil/water dripping off it slightly. The rocker assembly however doesn't have any mayo on it anymore, and no signs of rust are present (last time i took off the rocker cover, the rockers were slightly rusted).

I am not sure whether the rocker cover mayo appeared now or whether it was there before, but bottom line is there was some mayo there!

Engine is NOT down on power at all. Head gasket was changed and compression shows 185-180-180-180 so i'm led to believe the head gasket is okay between the cylinders, so I don't see why it wouldn't be between oil/waterways.

Dipstick has absolutely no traces of water on it (i was told to check that by someone because if it had mayo on it, then i definitely had a problem).

I'm tempted to clean the rocker cover tomorrow morning and take the car for a 100 mile drive and see what happens. Any harm in doing that?

[Pavel]

Another thing! Assuming the mayo is still present, i'll have to take off the head. If the gasket appears to be alright, can i reuse it since it's only been on the car for a week? I am REALLY not enthused at the idea of ordering another gasket :erm: This engine is going, but i can't sell a knackered lump (even though it runs pretty damn sweet right now).

[clubman katie B.F]

I have been a chef for 18 years, and to make mayo you ned to emulsify something and oil, in this case water and oil.....so somewhere down the line you have got a leak, with you water and your oil. i would definitely not use the head gasket again. by the sound of things, that head is going to have to come off,if you do that (which we did at the showdown!!!) you must must get a new gasket, or you will be making more mayo!!!!

[siggy]

Clean the rocker cover and run it again. Its very unlikely thats is a problem after only 5 miles. Unless you have loss most of the water into the engine.

Siggy

[Dan]

If you have already changed your head gasket once and that hasn't cured the problem I can see why you don't want to pull it again.

Get your cooling system pressure tested by your local garage. This is the only real way to see whether there is a leak or if the water is left over from before or coming from somewhere else. But it does sound like you have a cracked casting somewhere I'm afraid.

Definitely always use a new head gasket, unless it's a multilayer copper jobie designed to be used a couple of times. Even they don't efectively re-seal after they've been on a few weeks.

[siggy]

Presure testing the cooling system would be a waste of time and money, it will not show you leaks from the system into the engine.

He can't remember if he cleaned the cover.

Siggy

[dklawson]

As Siggy said, since you don't know how long the emulsion was in the rocker cover most testing is a waste of time and money. Clean it out thoroughly now and take note of your coolant level and condition. Monitor it and your oil over several weeks of driving while watching for the problem to reappear.

In the U.S. this condition is farily common on A-series engines which are run in cool-damp fall, winter, and spring morning and NOT given enough of a drive to warm the engine properly. Humidity in the air condenses in the rocker cover and gets mixed with the oil. It's more common on high-mileage engines but it isn't formed because of water leaks or blown head gaskets. If you drive only a couple of miles and stop your car... expect this emulsion to reappear in cool weather.

[Dan]

I would not have suggested the expense of a test if this was the first time Pavel had raised this point, but since he first spoke about this a couple of weeks ago and has been unable to solve the problem with the first batch of answers I really think he should have this looked into by a mechanic.

What DK says is quite a good point though, I know that since you live on the surface of the sun it can't be said that you have cool weather Pavel, but did you do this test run early in the morning? The weather in Cyprus in the early morning, even in July would be about right for condensation to be drawn through the rocker cap by the crankcase ventilation system.

[Pavel]

Actually dk has struck a very good point i think. In the last 6 months the car may have been run for only about 10-15 miles!!!!

And most of this was after changing the head gasket, so I'm tempted to think that it's just humidity that got under there while changing the gasket (engine was standing without a rocker cover, just a newspaper covering the rocker assembly for a few days).

This problem never occured before, and it just happened after the head gasket change so I doubt it would be a cracked casing. I'll run the car around a lot this week after cleaning the rocker cover, if it disappears, then great. if not ill pull the head probably (or just run the engine till it blows up )

Thanks for all the replies everyone, I think this is one of the most in-depth tecnhnical threads i've seen recently!

[siggy]

DK we have the same problem here with emulsion in the oil probably more so than you do, our cars tend to travel much shorter distances and often never get to the correct running temp.

Dan a coolant presure test would not show anything that would help Pavel, unless there was a very bad leak across the water jacket to the oil gallieries. I that case the water would show up mixed with the oil, not a emulsion inside the R/cover.

Incedentally the weather in Cyprus in the early part of the year can change from hot at the coast to cold. There is a ski centre in the Trudos mountings. Last time we were there it was sunbathing in Pathos and 4 foot of snow 50 miles away at Trudos.

Siggy