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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Coolant Milky White, Oil is not

  • Thread starter Thread starter 01Stang65
  • Start date Start date Oct 30, 2020
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01Stang65

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Jan 19, 2017
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Oct 30, 2020
#1
  • Oct 30, 2020
  • #1
So I just swapped a new 4.6 2v motor into my 01 GT, and filled up with new coolant obviously. After less than 20 drives, the coolant looks super milky white, not even a hint of green. The car is blowing off alot of steam/clouds from the engine area and I can't tell where it is coming from. I think its coming from the headers.

Previously when installing the motor I removed the valve covers to paint them and reinstalled. I messed up the gasket a couple times and finally got it right the 3rd time. So I initially thought the steam was the dripping oil burning off the headers, but again that was 15 drives ago, shouldn't that have cleared up by now?

The oil seems to be clean. The coolant is not. Whats going on here?
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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Kearney, NE
Oct 30, 2020
#2
  • Oct 30, 2020
  • #2
How is the gasket on the oil filter adaptor?
The o ring like thing was the issue when I had oil on my coolant.
 
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01Stang65

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Jan 19, 2017
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Oct 30, 2020
#3
  • Oct 30, 2020
  • #3
7991LXnSHO said:
How is the gasket on the oil filter adaptor?
The o ring like thing was the issue when I had oil on my coolant.
Click to expand...
When I got the new
 
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01Stang65

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Jan 19, 2017
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Oct 30, 2020
#4
  • Oct 30, 2020
  • #4
7991LXnSHO said:
How is the gasket on the oil filter adaptor?
The o ring like thing was the issue when I had oil on my coolant.
Click to expand...
When I got the new motor I replaced all the external gaskets, even though it only has 30k miles on it. I know for a fact I did that one right.

Strange... When I first got engine swapped and took it out for a drive, the coolant res was just slightly low because that's all I had on hand. I only drove it a few times like that, today I check it and it's super milky. After the engine cooled down and the coolant settled, the res was completely empty. A friend told me to fill it up, run the car and see if it bubbles, it didn't.
 

TIGGER

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Nov 4, 2020
#5
  • Nov 4, 2020
  • #5
I would check or replace your oil cooler gaskets to see if they have failed. I think that is what 7991LXnSHO is referring too. Good luck
 
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01Stang65

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Jan 19, 2017
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Nov 4, 2020
#6
  • Nov 4, 2020
  • #6
TIGGER said:
I would check or replace your oil cooler gaskets to see if they have failed. I think that is what 7991LXnSHO is referring too. Good luck
Click to expand...
So a couple things I noticed after driving it for a few days...

-I think previous coolant levels were so low, that whatever residue was in the engine from sitting before it went in my car just got mixed with the low amount of coolant and turned it milky white.
-I filled the coolant the rest of the way and sure enough returned it to it's green color. After driving it for a few days it has stayed green and not lost it's level.

Alot of times it's the easy stupid mistakes, glad I tested more before just assuming a gasket leak.
 

TIGGER

Founding Member
Mar 6, 2000
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Portland, OR
Nov 4, 2020
#7
  • Nov 4, 2020
  • #7
So no more steam from the engine? I would still drain and flush the cooling system just to make sure there is clean coolant in the motor. I would not want to run that muck thru my cooling system for very long.
 
Reactions: 7991LXnSHO
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01Stang65

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Jan 19, 2017
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Nov 4, 2020
#8
  • Nov 4, 2020
  • #8
TIGGER said:
So no more steam from the engine? I would still drain and flush the cooling system just to make sure there is clean coolant in the motor. I would not want to run that muck thru my cooling system for very long.
Click to expand...
I'm going to drain it tomorrow... The steam was valve cover gasket and I fixed that. All troubleshooting things with this new engine. I'm sure there will be more hiccups the more I drive the car.
 
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