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White crap under my oil cap?

  • Thread starter Thread starter Gixxer976
  • Start date Start date Jan 30, 2006
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Gixxer976

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Hey everyone. I have a 2003 Gt with 18k on the clock. The car runs perfect and is only drivin on the weekends. I was changing the oil when i noticed on the underside of the oil cap there was a white oil substance and It got me a little worried, but the car runs fine So has anyone ever seen this before?
Thanks
 

Nater

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I've seen it on all my cars and am not worried about it. Don't know why it shows up but it does. I wipe it off and do not worry about it.
 
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Tommy 00GT

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water mixed with oil will give you that white substance. so you may have a problem
 
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Uncle Meat

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Jan 30, 2006
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Tommy 00GT said:
water mixed with oil will give you that white substance. so you may have a problem
Click to expand...
QFT! If you haven't added any "Additives" to your oil and you find a white creamy substance under the oil cap you have an oil contamination of some sort. Usually it's from a leaking head gasket which allows coolant to pollute the oil. You need to get it checked out ASAP!

U.M.
 

Nater

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Then it must have been a problem on every car that I've owned. I would think that it's the water from condensation inside the engine. Once the engine warms up, vaporizes the water, it hits the highest part it can go and condenses. Thus a white, milky substance on the oil cap.
 
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Uncle Meat

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Nater said:
Then it must have been a problem on every car that I've owned. I would think that it's the water from condensation inside the engine. Once the engine warms up, vaporizes the water, it hits the highest part it can go and condenses. Thus a white, milky substance on the oil cap.
Click to expand...
None of my vehicles have that cream under their oil caps and the only ones that I've seen which do have it were running what we found to be contaminated oil! Maybe we need to have a poll? Ask everyone to run outside and check their caps.

U.M.
 

FORCED2DV8

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Hold on! here... Of course it can be caused by coolant or water in the oil, so maybe head gasket or seal somewhere, It can also be caused by changing brands of oil back and forth, valvoline 1 time then next time castrol, then back to valvoline, can also cause white or discoloration in the oil, First find out a few things, Compression Test, Is the car using coolant? What does the oil look like when you change it?? You may just need to change the oil and stay with the same brand.
 
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Uncle Meat

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FORCED2DV8 said:
Hold on! here... Of course it can be caused by coolant or water in the oil, so maybe head gasket or seal somewhere, It can also be caused by changing brands of oil back and forth, valvoline 1 time then next time castrol, then back to valvoline, can also cause white or discoloration in the oil.
Click to expand...
First I've ever heard of that being the cause...

U.M.
 

sgarlic

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Don't start freaking out and do a head gasket swap. Just wipe it off, then just check it again at next oil change. If it's white again in 3k miles, then maybe you should look in to it more.

Switching oil types has nothing to do with it. I just ran out and checked mine, there's no white on there @ 8k.
 

FORCED2DV8

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Uncle Meat said:
First I've ever heard of that being the cause...

U.M.
Click to expand...

I worded that wrong, Some add oil to there car if its low, say you have valvoline in it the to bring it back to full they pour in a qt. of penzoil, and so on, this can create the discoloration in the oil..
 
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Uncle Meat

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#11
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Poll is up.... just for S&G's...

http://eleanor.pro3i.com/showthread.php?t=612109

U.M.
 

Nater

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Also consideration must be made due to the difference in temperatures. I would venture to say that those in the south would not experience this as much as those in the north. Why? Because it's colder here. BTW, just checked mine, white residue and it smells like Mobil 1. No issues with losing oil or coolant, the tailpipes are still clean and the engine runs great! When I do oil changes, I always wipe it off.
 
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n0v8or

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Aug 23, 2003
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#13
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You asked: "Has anyone seen this before?"

Heck yes. On all of my cars, back to 1965, that were stored outside overnight in Winter and used infrequently and/or primarily for trips of less than 20 miles. As others suggested, it comes from condensation of moisture in the air on the metal surfaces of the crankcase. I would expect it to be more prevalent in places like Seattle and southern New England with frequent high dew points. When you go out in the morning, if there is frost or water on your sheet metal, depite no rain or snow the previous 24 hours, there is also water (consdensed moisture) in places you cannot see.

The only solution I have found is to change the oil more often when the car is not used every day. I don't drive my GT much in Winter either, so my Spring oil change ends up being a 1500 mile instead of a 5000 mile change.
 

timeless2

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I've seen it before, but it is not present on my 2004. It is driven daily, 250 miles per week.
 

Nater

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4u2nv said:
I've seen it before, but it is not present on my 2004. It is driven daily, 250 miles per week.
Click to expand...

Now you have. Took it about 10 minutes ago. I drive 250-300 miles a week.

View attachment 489273
 
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Gixxer976

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Dec 16, 2005
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Jan 30, 2006
#16
  • Jan 30, 2006
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Hey thanks everyone for taking the time to help me out with the poll and pics.
^
^
That is exactly what I was talking about in the picture.
The car does sit in 30 to 40 degree weather without moving during the week.
And I only drive about 50 to 100 miles over the weekend if that. My warrenty is still good till october of this year so If it becomes a problem I will have it looked at.
 

jstreet0204

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#17
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Change the oil and look at it. If the oil in the pan is contaminated like that you have a problem. If not, it is likely just condensation.
 

CanadaStang

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It's caused by condensation from driving in a cold climate, but yes a coolant leak will do this too.
 
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Tommy 00GT

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Jan 30, 2006
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Nater said:
Now you have. Took it about 10 minutes ago. I drive 250-300 miles a week.

View attachment 489265
Click to expand...




when you said milky white i didn't realize there was that much under the cap. I have never seen anytihng like that on my mustang or any other cars I have owned
 

Nater

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#20
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Tommy 00GT said:


when you said milky white i didn't realize there was that much under the cap. I have never seen anytihng like that on my mustang or any other cars I have owned
Click to expand...

I would believe the keyword is "CA" as noted in your location. There really is not that much. When the oil is drained for an oil change it comes out a dark brown/black. I've never worried about it.
 
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