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  • 1996 - 2004 SN95 Mustang -General/Talk-

What is this on my oil cap?

  • Thread starter Thread starter bonestock87
  • Start date Start date Dec 31, 2010

bonestock87

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Dec 19, 2001
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Cape Coral, FL
Dec 31, 2010
#1
  • Dec 31, 2010
  • #1
Went to change my oil today and when I open the oil fill this is what I find:


It's been a year since the oil was changed, but less than 4k miles. I use Motorcraft 5W20 Synthetic Blend and have since I've owned it beginning at 29k miles, it now has 67k miles. As far as I could tell there was none of this down in the motor and the oil that came out of the pan was fine, just black. My father-in-law says he thinks its from the oil breaking down from being old. Any thoughts? Here is a pic down inside:
 

KBExperience

Active Member
Jun 21, 2009
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Houston
Dec 31, 2010
#2
  • Dec 31, 2010
  • #2
Looks like coolant is making it's way in to your oil somehow. Might be a blown gasket somewhere.


But it could also just be condensation from the heat of the engine.
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
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Chicagoland
Dec 31, 2010
#3
  • Dec 31, 2010
  • #3
Most likely it's condensation. If you're not seeing the milkshake down in the pan, that's probably just where condensation has accumulated inside the engine. Does it come up to operating temperature every time you drive it, or does it sometimes get short trips?
 

bonestock87

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Dec 19, 2001
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Cape Coral, FL
Dec 31, 2010
#4
  • Dec 31, 2010
  • #4
Short trips most of the time. I typically drive my '93 4-banger to work but it's down right now, so for the last month I've been driving the '03. Work is only 6.5 miles away, I consider that a short trip. The father-in-law said condensation too. I can confidentaly say none of this came out of the oil pan.
 

KBExperience

Active Member
Jun 21, 2009
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Houston
Dec 31, 2010
#5
  • Dec 31, 2010
  • #5
But from the looks of those cams it's coolant getting in to the engine.. What did the oil look like when you changed it?
 
N

ninjastang125

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Nov 1, 2008
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maryland
Dec 31, 2010
#6
  • Dec 31, 2010
  • #6
Peanut butterrr? Yummy
 

CobraRed_96_GT

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Dec 31, 2010
#7
  • Dec 31, 2010
  • #7
I've seen threads like this before where there was no coolant leak, but that does look like a lot.
 

merc123

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Jan 27, 2003
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Dec 31, 2010
#8
  • Dec 31, 2010
  • #8
Looks to me like more than condensation. Might not be a bad idea to pull a valve cover and see if there is any milking in the galleys.
 

Crzyhrse

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Dec 23, 2004
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Seattle, WA
Dec 31, 2010
#9
  • Dec 31, 2010
  • #9
Man, if anyone should have that crap in their oil fill area then it's my Mach. It gets almost nothing but short trips and sits alot. Never seen it though.
 
D

darkside03gt

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Sacramento CA
Dec 31, 2010
#10
  • Dec 31, 2010
  • #10
It could be either condensation or the oil braking down. Just as a precaution I would check the coolant level and keep an eye on it.

I would yank both valve cover and take a look to see if that crap is in the valvetrain.

Also I would never leave oil in the car for an entire year regardless if I drove the car 2500 miles or 50. Its simply not a good idea and most oil makers say x miles or x months. Amsoil being the exception but I do believe that they even say if the vehicle sits to long change the oil.
 

Kdubslugga

Active Member
Jun 7, 2003
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Akron, OH
Dec 31, 2010
#11
  • Dec 31, 2010
  • #11
bonestock87 said:
Short trips most of the time. I typically drive my '93 4-banger to work but it's down right now, so for the last month I've been driving the '03. Work is only 6.5 miles away, I consider that a short trip. The father-in-law said condensation too. I can confidentaly say none of this came out of the oil pan.
Click to expand...


Yes thats all this is, nothin to worry about. very common
 

tag4car

Member
Nov 21, 2005
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Birmingham AL
Jan 1, 2011
#12
  • Jan 1, 2011
  • #12
might be a bad pcv valve doing some of it
 

LarsD

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Jan 1, 2011
#13
  • Jan 1, 2011
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Pull the stick, if it looks normal then likely it is just condensation.
 

bonestock87

Founding Member
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Cape Coral, FL
Jan 1, 2011
#14
  • Jan 1, 2011
  • #14
Pull the stick, if it looks normal then likely it is just condensation
Click to expand...
Everything looked normal.
Peanut butterrr? Yummy
Click to expand...
No, no, it didn't taste like peanut butter. More of a Wherther's Original flavor.
But from the looks of those cams it's coolant getting in to the engine.. What did the oil look like when you changed it?
Click to expand...
Completely clean cams = coolant in the engine? The oil came out of the pan looking completely normal, just a little darker than I have ever let it get.

I appreciate all the responses, I'm chalking it up to condensation. The goo was only at the very top of the oil fill neck and cap. I've only got 67k miles and I don't beat on the car, usually shifting at 2k rpm's. The coolant level is spot on as well. I will say I never intended to leave the oil in that long regardless of the mileage. Won't be doing that again.
 
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