sudden change in oil colour (and not a black colour either)
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- 850 Super
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sudden change in oil colour (and not a black colour either)
so...worringly, I checked my oil on Friday night and when i pulled the dipstick out and looked at it, i was shocked to see that the oil had turned an almost greyish colour. Previous weekend when it was last looked at...all perfect. Had not drivien since.
I looked under the oil cap..all looked fine.
Checked water levels...all fine.
I thought it might be a condensation issue.
Over the weekend, I had to drive the car to a show....rain, rain and more rain. Kept an eye on oil etc...and now mayo everywhere, but an ever so slightly more normal looking oil colour.
Both oil levels and water levels normal. Nothing out of the ordinary as far as engine performance, noises, knocking etc. No overheating, no smokey exhausts.
Spent remainder of weekend with the rest of the chaps up here thinking about what it could be....and one suggestion is that with all the rain about (and driving through it), it's sucking the water in from somewhere and that one culprit could be the large breather hose that i have coming out of the rocker cover, directly through the inner wing.
Does this sound plausible, or do i have a crisis looming?
I looked under the oil cap..all looked fine.
Checked water levels...all fine.
I thought it might be a condensation issue.
Over the weekend, I had to drive the car to a show....rain, rain and more rain. Kept an eye on oil etc...and now mayo everywhere, but an ever so slightly more normal looking oil colour.
Both oil levels and water levels normal. Nothing out of the ordinary as far as engine performance, noises, knocking etc. No overheating, no smokey exhausts.
Spent remainder of weekend with the rest of the chaps up here thinking about what it could be....and one suggestion is that with all the rain about (and driving through it), it's sucking the water in from somewhere and that one culprit could be the large breather hose that i have coming out of the rocker cover, directly through the inner wing.
Does this sound plausible, or do i have a crisis looming?
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- 998 Cooper
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Re: sudden change in oil colour (and not a black colour eith
You don't say how the breather hose ends..
-If it just ends in the wheel arch /house area, then it is likely that you will draw water/moisture in through the breather.
-If you have a filter on the end of the hose, then it should be less likely, but not impossible.
-If you have a catch-tank, then there could be water collecting in there (from the engine and from atmosphere), or, the breather pipe may be too far in the catch tank/bottle and drawing fluid back into the engine
You don't need much water in the oil to get mayonnaise, so coolant could be leaking in to the oil... (sorry, I know none of us want to hear that....) -you could check for combustion products in the coolant.
-Don't forget that a gasket might be leaking when the engine is cold, but seal when it warms up -so you might not see any cooling problems
I would try and keep the catch-tank in the engine-bay on a road car (For one thing, there are less likely to be air-pressure differences).
-If it just ends in the wheel arch /house area, then it is likely that you will draw water/moisture in through the breather.
-If you have a filter on the end of the hose, then it should be less likely, but not impossible.
-If you have a catch-tank, then there could be water collecting in there (from the engine and from atmosphere), or, the breather pipe may be too far in the catch tank/bottle and drawing fluid back into the engine
You don't need much water in the oil to get mayonnaise, so coolant could be leaking in to the oil... (sorry, I know none of us want to hear that....) -you could check for combustion products in the coolant.
-Don't forget that a gasket might be leaking when the engine is cold, but seal when it warms up -so you might not see any cooling problems
I would try and keep the catch-tank in the engine-bay on a road car (For one thing, there are less likely to be air-pressure differences).
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- 850 Super
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Re: sudden change in oil colour (and not a black colour eith
no catch tank (although perhaps I need to change that). There is a filter (of sorts) on the end of the hose, but I need to check it as it wouldn't be the first time that it's fallen out.andy1071 wrote:You don't say how the breather hose ends..
-If it just ends in the wheel arch /house area, then it is likely that you will draw water/moisture in through the breather.
-If you have a filter on the end of the hose, then it should be less likely, but not impossible.
-If you have a catch-tank, then there could be water collecting in there (from the engine and from atmosphere), or, the breather pipe may be too far in the catch tank/bottle and drawing fluid back into the engine
You don't need much water in the oil to get mayonnaise, so coolant could be leaking in to the oil... (sorry, I know none of us want to hear that....) -you could check for combustion products in the coolant.
-Don't forget that a gasket might be leaking when the engine is cold, but seal when it warms up -so you might not see any cooling problems
I would try and keep the catch-tank in the engine-bay on a road car (For one thing, there are less likely to be air-pressure differences).
I will relocate that particular breather pipe, flush out the engine, new oil in etc...and see what happens.
Am prepared for gasket issues...although obviously would love it not to be.
thnx.
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Re: sudden change in oil colour (and not a black colour eith
Ohh ooo ... sudden colour change = water in oil = blown head gasket ... 
Cheers, Ian

Cheers, Ian
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Re: sudden change in oil colour (and not a black colour eith
What type of oil are you using - I've had loads of trouble with semi synthetic stuff looking like it was sponsored by Hellmans, went back to pure mineral with no problems since, and yes the damp air does affect it. Found this on Mini's, LDVs and Land Rovers
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Re: sudden change in oil colour (and not a black colour eith
How much and how far has a big bearing on water in the oil as well, if you only do short journeys or just run the engine for while, the moisture in the air will mix with the oil (Yes I know it doesn't actually mix) and not get the chance to evaporate off when the oil gets up to operating temp. this is what causes most of the milky gunk in the rocker cover and cap. the hot oil with moisture in it gets thrown onto the cover which is usually cooler by virtue of being in the air stream and thin metal and the moisture condenses out..............
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Re: sudden change in oil colour (and not a black colour eith
Catmint wrote:What type of oil are you using - I've had loads of trouble with semi synthetic stuff looking like it was sponsored by Hellmans, went back to pure mineral with no problems since, and yes the damp air does affect it. Found this on Mini's, LDVs and Land Rovers
Valvoline VR1 20w50.
Admittedly, the car has done many v.short trips as well....it doesn't normally, but recently it has.
I'll do an oil change at the weekend and start to monitor the situation, to see what happens and when.
Like I said earlier...am prepared for the head to come off, but obviously want to eliminate other possibilities first.
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Re: sudden change in oil colour (and not a black colour eith
It sounds to me like that open ended breather and short journeys will be to blame from what you've described.
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Re: sudden change in oil colour (and not a black colour eith
VR1 is what I run now without problem in the mini.
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Re: sudden change in oil colour (and not a black colour eith
well...i've done a bit more investigation, but nothing really obvious so far.
oil now changed.
removed all the breathers and hoses, completely layered up in the stuff. Standing water in the hoses as well!! Mayo was covering the gauze/filter at the end of the external breather (under the inner wing)..which could have been blocking it.
Have run the engine for quite a while since oil change....no coolant loss. Can't see it bubbling either.
Did a compression test for a laugh....conistent all the way across. the engine (1330) does have high compression at 230psi...but it always has. so nothing has changed there.
i need to replace the rocker gasket...as I ruined it when i cleaned the rocker cover out...so no more testing until that is replaced.
am ordering new head gasket (just in case i need to go down that route), plus obviously rocker gasket.
oil now changed.
removed all the breathers and hoses, completely layered up in the stuff. Standing water in the hoses as well!! Mayo was covering the gauze/filter at the end of the external breather (under the inner wing)..which could have been blocking it.
Have run the engine for quite a while since oil change....no coolant loss. Can't see it bubbling either.
Did a compression test for a laugh....conistent all the way across. the engine (1330) does have high compression at 230psi...but it always has. so nothing has changed there.
i need to replace the rocker gasket...as I ruined it when i cleaned the rocker cover out...so no more testing until that is replaced.
am ordering new head gasket (just in case i need to go down that route), plus obviously rocker gasket.
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Re: sudden change in oil colour (and not a black colour eith
I think you've found the cause. Open Breathers.thefarmer wrote:
removed all the breathers and hoses, completely layered up in the stuff. Standing water in the hoses as well!! Mayo was covering the gauze/filter at the end of the external breather (under the inner wing)..