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Why oil seems to be almost "milky" after EFI swap?

  • Thread starter Thread starter monk302
  • Start date Start date Aug 27, 2006

monk302

Founding Member
Apr 18, 2001
742
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New Jersey
Aug 27, 2006
#1
  • Aug 27, 2006
  • #1
So I have be running my engine after having just completed my EFI swap. It appears as if the oil on the dipstick appears to be "milky." What would make this happen. Would it be from antifreeze somehow getting into the oil? I would appreciate any opinions.
 
G

gsxrken

Member
Sep 12, 2005
206
1
18
Weschester County, NY
Aug 27, 2006
#2
  • Aug 27, 2006
  • #2
yes, water from the intake is likely getting in. You probably need to reseal your intake manifold. Also make sure your thermostat is allowing the engine to come up to temp, around 180-190 F degrees or so.
 

krash kendall

Active Member
Nov 19, 2004
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Aldergrove, B.C. Canada
Aug 27, 2006
#3
  • Aug 27, 2006
  • #3
What year heads are using? If pre-1976 you will have to use early 302 intake gaskets. They should work fine with the later manifold, but the later gaskets will not work with the early heads.

Hey, 1000 posts!
 
6

66StangFastback

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Jun 6, 2005
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norman, oklahoma
Aug 27, 2006
#4
  • Aug 27, 2006
  • #4
I had a milky substance in my oil after rebuilding the engine. It was only the lube used on the bearings,cam and such though.
 

monk302

Founding Member
Apr 18, 2001
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New Jersey
Aug 27, 2006
#5
  • Aug 27, 2006
  • #5
krash kendall said:
What year heads are using? If pre-1976 you will have to use early 302 intake gaskets. They should work fine with the later manifold, but the later gaskets will not work with the early heads.

Hey, 1000 posts!
Click to expand...

Hey Krash,

I am using re-1976 heads. So you are saying I need pre-1976 gaskets huh. That may be the problem then. I have had issues with leaking antifreeze this entire time. I thought I solved it last time by repositioning the gasket but now I think the fluid may be instead going into the lifter valley.

Thanks,

Mike
 

krash kendall

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Aug 27, 2006
#6
  • Aug 27, 2006
  • #6
When you lay the later gaskets on the head they look like they are lining up with the end cooling journals, however there is less than 1/16" (if any) coverage. They will leak at the driver's side rear or passenger side front, most likely. My neighbour and I both made this mistake on our cars within a month of each other. He did it first, so he knew exactly what my problem was when it happened to me after putting a new intake and carb on.
 

monk302

Founding Member
Apr 18, 2001
742
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Aug 27, 2006
#7
  • Aug 27, 2006
  • #7
krash kendall said:
When you lay the later gaskets on the head they look like they are lining up with the end cooling journals, however there is less than 1/16" (if any) coverage. They will leak at the driver's side rear or passenger side front, most likely. My neighbour and I both made this mistake on our cars within a month of each other. He did it first, so he knew exactly what my problem was when it happened to me after putting a new intake and carb on.
Click to expand...

Precisely what happened to mine the first time I installed. Was leaking on the rear driver side. I guess now it is just flowing into the lifter valley area. Off to get new gaskets this week I guess.
 

krash kendall

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Aldergrove, B.C. Canada
Aug 30, 2006
#8
  • Aug 30, 2006
  • #8
Well, its been a few days now. Any progress?
 

monk302

Founding Member
Apr 18, 2001
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New Jersey
Aug 30, 2006
#9
  • Aug 30, 2006
  • #9
krash kendall said:
Well, its been a few days now. Any progress?
Click to expand...

Actually going to take the top end of the engine off this afternoon with the gaskets hopefully arriving around 4:30. Should have it back together sometime tomorrow. I will keep ya filled in.
 

monk302

Founding Member
Apr 18, 2001
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Aug 31, 2006
#10
  • Aug 31, 2006
  • #10
So today I bought a case of some generic motor oil and Marvel Mystery Oil. Got home and drained my oil pan and immediately antifreeze came out for a few seconds followed by my "milky oil." Took off filter, put new one on, and then put five new quarts of generic oil in along with Marvel Mystery Oil. I ran it for about 15 mins and tomorrow I am going to drain oil, put another filter on, put good Exxon Oil in and hope for the best.
 

krash kendall

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Nov 19, 2004
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Sep 1, 2006
#11
  • Sep 1, 2006
  • #11
But you didn't change the gaskets?

Pouring some magic elixer into the sump won't "fix" anything. If there is enough coolant getting in the pan for it to stratify in the manner you describe then you run a high risk of hydraulic-ing the motor and destroying it.
 
6

66moneypit

Member
Dec 28, 2004
536
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Northern Va
Sep 1, 2006
#12
  • Sep 1, 2006
  • #12
That mystery oil probably isn't going to fix the problem.

Now it is possible that you got alot of antifreeze in the lifter valley when you took the old intake off. It's definitely a good idea to change the oil when you change the intake for that reason. I don't know if you could get enough to cause the milky oil though.

I would definitely redo the intake. It's a pain but worth it. My concern with that mystery oil is.....if it's stopping the leak...what else is it stopping ?
 
S

Steve69

Member
May 11, 2005
233
0
16
Sep 1, 2006
#13
  • Sep 1, 2006
  • #13
Did you get your engine up to temprature. Mine had the same thing
And I thought it was the manifold also. It was just alot of cold starts
and Idle time that caused my problem. As soon as my Mustang was road
worthy I changed the oil and ran it on the highway and never had the
problem again. I would try this first before taking the manifold off.
 
6

66moneypit

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536
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Northern Va
Sep 1, 2006
#14
  • Sep 1, 2006
  • #14
That's a good point, you might try getting it up to temp and then retorque your intake bolts. Mine settled and needed to be retightened a few times.
 

krash kendall

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Sep 1, 2006
#15
  • Sep 1, 2006
  • #15
Guys, he had a stratified layer of antifreeze under the oil that took a few seconds to pour out before he saw any oil. This is not a condensation issue. I guarrantee he has the wrong intake gaskets for those heads!
 

monk302

Founding Member
Apr 18, 2001
742
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16
New Jersey
Sep 1, 2006
#16
  • Sep 1, 2006
  • #16
krash kendall said:
Guys, he had a stratified layer of antifreeze under the oil that took a few seconds to pour out before he saw any oil. This is not a condensation issue. I guarrantee he has the wrong intake gaskets for those heads!
Click to expand...

Sorry for being unclear. I did take off the manifold and replace the gasket with a pre-1976 gasket. Then, from that point I have run the oil and plan on replacing it again this evening. So far I have not seen any indications of coolant leak since I have replaced the gasket. Krash was right on the money.
 

krash kendall

Active Member
Nov 19, 2004
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Aldergrove, B.C. Canada
Sep 5, 2006
#17
  • Sep 5, 2006
  • #17
Phew! You had me worried there!
 
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