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  • Fox 5.0 Mustang Tech

Headers Still Leaking......

  • Thread starter Thread starter PuppyDawg
  • Start date Start date Aug 18, 2004
P

PuppyDawg

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Nov 20, 2003
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Boston,MA
Aug 18, 2004
#1
  • Aug 18, 2004
  • #1
Hey guys....i just put my BBK headers (chrome shorties) on with the Fel Pro 1415's gaskets AND locking header bolts (stage 8) and they still leak from the manifold.....any suggestions on what gaskets i should use now?
 
V

v8only

Active Member
Jul 3, 2003
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Aug 18, 2004
#2
  • Aug 18, 2004
  • #2
You shouldn't have leaking issues with good gaskets, and if your torqueing it evenly. you probably have bent flanges. are they the older bbks with mulitiple flanges, or is it one piece flange??? Measure all the surfaces with perfect and precise straightedge and see what is going on.
 
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PuppyDawg

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Nov 20, 2003
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Aug 18, 2004
#3
  • Aug 18, 2004
  • #3
v8only said:
You shouldn't have leaking issues with good gaskets, and if your torqueing it evenly. you probably have bent flanges. are they the older bbks with mulitiple flanges, or is it one piece flange??? Measure all the surfaces with perfect and precise straightedge and see what is going on.
Click to expand...

yea these were brand new (out of the box) headers, and it's a one piece flange, and that's what got me to assume that my gaskets were the issue....
 
V

v8only

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Jul 3, 2003
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Aug 18, 2004
#4
  • Aug 18, 2004
  • #4
brand new, they're probably ok. When we put our frpp headers on last weekend, it came with a tightening sequence, are you following that??? snug them down in the right sequence yet, but don't tighten any fully till the header is flush with the head, then snug them down in the proper sequence.
 
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PuppyDawg

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Aug 18, 2004
#5
  • Aug 18, 2004
  • #5
v8only said:
brand new, they're probably ok. When we put our frpp headers on last weekend, it came with a tightening sequence, are you following that??? snug them down in the right sequence yet, but don't tighten any fully till the header is flush with the head, then snug them down in the proper sequence.
Click to expand...

oh ok....let me try that....dang...so much involved with these headers...now i have to just wait til it cools down before i do anything...thanks a lot for the advice...
 
V

v8only

Active Member
Jul 3, 2003
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Aug 18, 2004
#6
  • Aug 18, 2004
  • #6
cool, good luck, let me know. whenever you are dealing with pressure sensitive things such as exhaust components, cylinder heads, intake manifolds, and the such, it's always good to go in the exact order specified, but most importantly, never snug down one bolt super tightly until they are all down. It's always good to get the entire piece seated, with all the bolts very lightely tightened initially, othewise you've got all the pressure initially on one bolt, while the whole rest of the header is loose.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 18, 2004
#7
  • Aug 18, 2004
  • #7
I'm with v8only - I always use a straight edge to check the flange(s) for true BEFORE putting the headers on. If the flange is warped (and many are even brand new), you'll play hell trying to tighten the warp out of it with the bolts. When mine aren't true, I take them to a machine shop and have them heat/straighten/mill to get a true surface. They always bolt right up and seal the first time.
 
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gopher_6_9

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Jun 16, 2003
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Aug 18, 2004
#8
  • Aug 18, 2004
  • #8
Cut between the tubes (I usually only do between the midle two) and use Percy's gaskets.
 
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PuppyDawg

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Aug 18, 2004
#9
  • Aug 18, 2004
  • #9
gopher_6_9 said:
Cut between the tubes (I usually only do between the midle two) and use Percy's gaskets.
Click to expand...
you mean cut between the actual flanges to seperate 'em? and percy's are better than fel pro 1415's?
 
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v8only

Active Member
Jul 3, 2003
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Aug 18, 2004
#10
  • Aug 18, 2004
  • #10
gopher_6_9 said:
Cut between the tubes (I usually only do between the midle two) and use Percy's gaskets.
Click to expand...

are you talking about cutting that one piece flange??? why don't you just buy a set of macs then!!! That one piece flange is what makes the headers so stable and resistent to warping.

I'd do as michael said, imo, that was a great suggestion, I'll have to remember the machine shop deal next time i've got a stubborn set of headers.
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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Stafford,VA
Aug 18, 2004
#11
  • Aug 18, 2004
  • #11
did you scrape the head off with a razor???? gaskets wont seal good if there is alot of carbon or possible gasket left over.???
 

N8Miller

I need NOS....make it 2 of the big ones
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Jul 26, 2000
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Kingston, PA, USA
Aug 18, 2004
#12
  • Aug 18, 2004
  • #12
i am having the same problem with my longtubes...... where do yours leak from? mine is in the very rear....which is why i thought i might have a blown/cracked head gasket. whats the best replacement header gasket to get.
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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Stafford,VA
Aug 18, 2004
#13
  • Aug 18, 2004
  • #13
anything fel-pro is good................
 
K

kn7671

New Member
Aug 18, 2004
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Arlington, TX
Aug 18, 2004
#14
  • Aug 18, 2004
  • #14
I would bet the headers are not flat, even if they are new. I ran a set of MAC's for over 2 years without issues leaking, until the bolts loosened, then I could just re-tighten and then all was OK.
 
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