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1987 ford 5.0 SO Oil Leak Question

  • Thread starter Thread starter Jpc647
  • Start date Start date Aug 2, 2010
J

Jpc647

New Member
Aug 2, 2010
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Aug 2, 2010
#1
  • Aug 2, 2010
  • #1
1987 ford 5.0 SO Oil Leak (PCV Valve) Question

Hey Guys, I have a 1988 Thunderbird, I know its not a mustang, but its a fox body car, and it has a 1987 SO motor in it. I'm hoping with the large concentration of Ford 5.0's in this community, someone might be willing to help me.

There is oil coming up through the pcv valve/screen, into the line that connects to the plenum, and dripping down onto the valve cover. I was told the PCV valve was clogged, so I replaced it to no avail. I replaced the screen and the grommet at the same time. I then proceeded to change the intake gasket, thinking the defective PCV valve had blown out the end seal. The plugs are clean, so I am ruling out blowby, and the vent tube going from the oil fill neck to the upper intake is clear. Anyone have any idea why this oil is still coming up? The PCV valve and grommet pull out of their hole very easily, the grommet doesn't seat snug in there, could this be the problem? I thought with a large 5.0 crowd here someone might now, even if my engine isn't and H.O. like the mustangs were.

Picture of where is leaks from: http://i478.photobucket.com/albums/r...7/DSC01173.jpg.. Again this line is the end of the line the PCV valve connects to.

Please assist.
 

LX302

Stanger
Founding Member
Feb 29, 2000
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Bethlehem PA
Aug 3, 2010
#2
  • Aug 3, 2010
  • #2
You can have excessive blowby, meaning the piston rings are worn.
Do a compression test and post the results of each cylinder.

The valve just "sits" in the hole, so it shouldn't be super tight, it's normal from what your experiencing.
 
J

Jpc647

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Aug 2, 2010
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Aug 4, 2010
#3
  • Aug 4, 2010
  • #3
If it was blowby, wouldn't the car be smoking out the exhaust? Wouldn't the plug have an oil residue on them? I would think for the amount that would have to blowby to get the oil leakage here, the plugs would foul or at bare minimum have a residue. Am I wrong to think this?
 
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