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Leaking Oil Without the PCV

  • Thread starter Thread starter clay37355
  • Start date Start date Dec 23, 2010
C

clay37355

New Member
Jun 20, 2004
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Dec 23, 2010
#1
  • Dec 23, 2010
  • #1
I seem to be leaking some oil out of the front main seal. I bought a new Race Demon carb. The new carb didn't have the vacuum ports. I drilled the intake and installed a fitting to hook up my modulator for the c4 transmission. I was planning on just running Breathers on the valve covers and no pcv. When I do this though I have the leak. I assume the motor is building up too much crankcase pressure and pushing oil out of the front seal?? Am i going to have to drill another port in the intake? I could use the knockouts on the air cleaner and run the valve cover breather to that, but I am afraid that it will not create enough vacuum to stop the leak. Also, to my thinking, I really would rather not have the contaminated air going down through the carb. Anyone else run into this before? The motor is 351w based 393 stroker.
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Dec 23, 2010
#2
  • Dec 23, 2010
  • #2
Something like this may help you out.

Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Dec 23, 2010
#3
  • Dec 23, 2010
  • #3
clay37355 said:
I seem to be leaking some oil out of the front main seal. I bought a new Race Demon carb. The new carb didn't have the vacuum ports. I drilled the intake and installed a fitting to hook up my modulator for the c4 transmission. I was planning on just running Breathers on the valve covers and no pcv. When I do this though I have the leak. I assume the motor is building up too much crankcase pressure and pushing oil out of the front seal?? Am i going to have to drill another port in the intake? I could use the knockouts on the air cleaner and run the valve cover breather to that, but I am afraid that it will not create enough vacuum to stop the leak. Also, to my thinking, I really would rather not have the contaminated air going down through the carb. Anyone else run into this before? The motor is 351w based 393 stroker.
Click to expand...

Bud,
Don't worry about contamination. If your engine was built professionally, you don't have the blow by that creates the contamination. You need to run a VC pcv. This can come in the form of a breather with a built-in PCV, east to find. Buy that carb spacer for the PCV hook up as a minimum. Next from the the driver's side VC portal, add a breather with an inlet and route to the air cleaner. The result will be reducing any "normal" crank case pressures, not to mention reducing oil leak tendencies.
Good Luck!
 
K

KreagerM

Member
Nov 24, 2005
88
0
6
Maryland
Dec 24, 2010
#4
  • Dec 24, 2010
  • #4
As mentioned adding the PCV should eliminate your leaking issue. I know it cured mine and my buddy is having the same issue with his, so this winter we will get him straightened out.
 
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