Crankcase Water Vapour

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Oneball
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Crankcase Water Vapour

Post by Oneball »

Started the car for the first time since before Christmas and noticed a lot of water vapour out of the breather, took the filer off and I’d describe it as billowing out.

Drained some of the oil and there was a little bit of water in there, see photo below. I’ve pressure tested the cooling system both with coolant and air and there don’t appear to be any leaks.

Do you think this is just condensation or something more?
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Peter Laidler
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Re: Crankcase Water Vapour

Post by Peter Laidler »

Nope..... If you've got water in the oil and you have identified it as water, guess what? It is water leeching into the oil SOMEWHERE. Pressure testing the coolant system is the way to go. Pressurise ot to normal pressure on the gauge and leave it. If it's leeching out, there's the problem.

What about oil in the water? Any sign of that mayonnaise stuff emulsifying the oil, around the filler cap
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timmy201
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Re: Crankcase Water Vapour

Post by timmy201 »

Depending on your climate it can definitely be condensation, especially if you haven’t started it for a while

I’d refill and go again and keep an eye on it. I had a catch tank on my breathers and it’d get a decent bit of water in it
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Re: Crankcase Water Vapour

Post by Oneball »

There’s no mayonnaise and I’ve pressurised it to 15 psi and left it and it’s not lost any pressure. I also tried it with no coolant in there and pressurised it with air in case I could hear anything and again nothing. I’m at a bit of a loss to explain it really. There’s no evidence of head gasket failure and no reduction in coolant level, there’s no oil in the water.
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Re: Crankcase Water Vapour

Post by Catmint »

What oil are you using - semi synthetic is hydroscopic and can cause really bad "mayonaise" if you run it - found out that out the hard way and went back to mineral oil and not a problem now.
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Re: Crankcase Water Vapour

Post by Oneball »

It’s got Valvoline VR1 in it.
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Re: Crankcase Water Vapour

Post by wantafaster1 »

Yes I've had this with Valvoline, my theory is that because it's good oil it doesn't get so hot.

I don't think you have anything to worry about.
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