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Sick and tired of header leaks...please help!

  • Thread starter Thread starter 91LX_5L
  • Start date Start date Apr 21, 2005

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Apr 21, 2005
#1
  • Apr 21, 2005
  • #1
Well I just changed my header gasket (pass side) for the 2nd time and now there leaking again. The first time I had the mr gasket paper gaskets and they didnt last that long. This last time (2 weeks ago) I put in the felpro ones which have that little bit of aluminum on one side or what ever. I also took it for a drive tighted em down and it was fine. Next day tightend them again then a week later once again and now there leaking. I tryed to tighten them as tight as possible but its no good.

Anyways there leaking again... . It really drives me crazy.

Are there any ideas of how to get this bastard to stop leaking? The headers are like 6 months old so they should be fine.

How tight should I tighten the gasket? pretty much as tight as possible? should I tighten one bolt at a time starting from the middle, or tighten them all a bit starting from the middle out? please help!!!

I was thinking of these gaskets:
http://cgi.ebay.com/ebaymotors/ws/e...tem=7969291096&category=33666&sspagename=WDVW

Also my bolts are now getting worn and when I try to tighten them they slip. I was thinking of getting new bolts if I were to do I want 1" long or 3/4" long?
http://cgi.ebay.com/ebaymotors/ws/e...d=1,1&item=7969152861&sspagename=STRK:MEWA:IT

Thanks in advance!
Matt
 
W

WhiteHeat306

Member
Nov 28, 2004
283
1
16
Philadelphia Suburbs
Apr 21, 2005
#2
  • Apr 21, 2005
  • #2
I would try copper header gaskets, with ARP bolts and lock washers. And make sure you use some good loctite on those bolts. Everything will probably run about $125, but that beats swappin out your header gaskets every couple of months.

Edit: I just clicked on those ebay links. Those copper gaskets look good! Not sure about those JDI bolts, never used 'em. I recommended the ARP bolts because I have had a good experience with them. They are expensive though! You will be happy with those gaskets.
 

Stangfreak95

add a 4
Founding Member
Nov 4, 2002
3,571
0
0
In your sister. If none, your mom
Apr 21, 2005
#3
  • Apr 21, 2005
  • #3
The felpro gaskets are fine. The problems is your bolts. Get some STAGE-8 locking bolts. I guarantee you they will not loose up, if you put them correctly. I'm sorry I dont have a part number for you or the bolt measure either..
 

Blk05Retro

Member
Mar 31, 2005
99
0
6
Katy, TX
Apr 21, 2005
#4
  • Apr 21, 2005
  • #4
Get you some locking header bolts from FPR. Those little things won't loose up anymore. Just make sure they will work with your headers.
 

RIO5.0

15 Year Member
Feb 16, 2001
6,892
8
128
N.H.
Apr 21, 2005
#5
  • Apr 21, 2005
  • #5
Fel-Pro 1415 and Stg 8 #8913A with my Mac LTs....leakfree...
 

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Apr 21, 2005
#6
  • Apr 21, 2005
  • #6
well mine never really come loose either, they can just use about 1/8th of a turn the first time is all it really needed it after the short drive. I've heard there just a hassle. It doesnt seem that the bolts comming loose is my problem. Mabye the install is...

anyways with the fel-pros do I put the aluminum side against the header or the head?

also how tight should I tighten them, using the felpros?

its just my ONE SIDE that is leaking.

Thanks,
Matt
 

94gts

Member
Jul 4, 2004
873
0
16
Carmel, New York
Apr 21, 2005
#7
  • Apr 21, 2005
  • #7
i use some reall cool 1/8 in thick xtra thick gaskets. i can give you exact pecs if ya want them
 

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Apr 21, 2005
#8
  • Apr 21, 2005
  • #8
well what about doubling up some felpros with the aluminium side on both sides?

thanks
matt
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Apr 21, 2005
#9
  • Apr 21, 2005
  • #9
Unless you have a header flange that is warped the prob is not the gasket.

The prob is the bolts back out due to the heat then cold, heat then cold thing.

After the bolts loosen the exhaust pressure blows the gasket away cause the header is no longer tight against the head.

I use nothing more than lock washers to keep the bolts tight.

I put my combo together a little over two years ago and all I did was tighten the header bolts after a couple heat cycles and all has been good since then.

If you use nothing but the bolt supplied with the headers you have no way to keep the bolt tight. They will back off for sure.

Later
Grady
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Apr 21, 2005
#10
  • Apr 21, 2005
  • #10
I use stock bolts and normal gaskets, no fancy stuff for me! I can honestly say in all the different cars I've had headers on and all the different headers I've had, I've never lost a gasket. I've even reused them!

Since you're tightenting and retightening them good, the next thing I suspect is cleanliness of the head surface. When I do mine, I work at it to get it as clean as possible. Aside from these two things, I see no other reason why you'd lose a gasket (unless something is warped as mentioned above).
 

davins130

New Member
May 21, 2004
424
0
0
Apr 21, 2005
#11
  • Apr 21, 2005
  • #11
what side is it? are you 100 percent sure its the header leaking? i had a my air tube plugged when i removed my air pump and it sounded just like an exhaust leak, combined with the leaking egr valve smell and i swore it was the header gasket untill i replaced it and then realized how much of an idiot i was to not notice what it was, or you probly have a warped header or something because your gasket should not keep blowing out
 

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Apr 22, 2005
#12
  • Apr 22, 2005
  • #12
im almost postive its my header.

so final5-0 are you saying to just use normal lock washers (.02cents)? whats wrong with the bolts they supply or the BBK/MAC header bolts? I was thinking of getting these because my BBK bolts are starting to get rounded from all the awkward tightning and loosining they got on them.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7969152861&ssPageName=STRK:MEWA:IT

Should I get 3/4" or 1"?

Thanks
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Apr 22, 2005
#13
  • Apr 22, 2005
  • #13
91LX_5L said:
im almost postive its my header.

so final5-0 are you saying to just use normal lock washers (.02cents)? whats wrong with the bolts they supply or the BBK/MAC header bolts? I was thinking of getting these because my BBK bolts are starting to get rounded from all the awkward tightning and loosining they got on them.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7969152861&ssPageName=STRK:MEWA:IT

Should I get 3/4" or 1"?

Thanks
Click to expand...

I think you said you did not believe your bolts were backing off. If that is the case then the flange is not sitting flat next to the head.

Is the header sitting on anything that would cause this to happen?

Is your mid pipe supported by its hanger which will keep the system from moving around and causing leaks?

You said it is only on one side ........ is the motor mount on that same side loose or broken?

If the exhaust system is moving or shaking around the bolts will not stay tight.

Again the bolts get heat cycled each time you fire up the motor and that can cause them to back off a bit.

If you wanna try the lock washer thing here is a thought or two for you.

I usually find them at a bolt supply house. Looking at them like you are looking through the hole ......... They are a bit thinner (the distance from outside of hole to outside of washer) than the kind of lock washer you typically see at the home improvment store.

As for the bolt length it depends on the thickness of your header flange, thickness of the lock washer, and depth of the bolt hole. Just take a bolt out and put a long nail as deep as it will go in the bolt hole and mark it next to the flange. Add the thickness of the lock washer and that is about the total distance of the whole deal. Find a bolt that is 1/8 to 1/4 of an inch shorter and you should be good to go.

If your heads are Aluminum don't go too tight and use some anti seize on the bolt threads.

Later
Grady
 

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Apr 22, 2005
#14
  • Apr 22, 2005
  • #14
thanks a lot

Ok about these felpro1415s are they aluminum both sides? the felpros I tried were some sort of aluminum one side then sorta paperish material the other, those the right ones? Just to confirm the alum goes on the header side correct?

Im going to take my header right off this time and see if its warped at all. If it is I think ill the copper silicone, do you think this might help? where should I run the silicone?
 

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Apr 22, 2005
#15
  • Apr 22, 2005
  • #15
anyone? know which way the felpros go on? are the alum both sides or just one side (1415s)
 

RIO5.0

15 Year Member
Feb 16, 2001
6,892
8
128
N.H.
Apr 22, 2005
#16
  • Apr 22, 2005
  • #16
The 1415 are just gasket material, Black, both sides...I think the "fel-pro" writing goes out....
Their nice as you just install your headers loosely with the end bolts...these have channels on the ends that slip over the end bolts...just feed the rest in then tighten down...I snug em good, take a ride to heat cycle them....retighten and put the lockers on...
Like Grady mentioned, I would check your flange faces and makes sure things are nice and flat....


Found this pic...you can see the gasket...nothing special but they seal well.

 

trickstang94

New Member
Nov 17, 2004
80
0
0
CA
Apr 22, 2005
#17
  • Apr 22, 2005
  • #17
If you want new bolts, go to www.summitracing.com and check out these new bada$$ bolts P/N BPP-200-077. Made by Breslin. Only $63.00. I just ordered them. I have the same problem of the header bolts coming loose and Im certain this will put and end to it.
 
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