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Exhaust Header Gasket

  • Thread starter Thread starter WonkeyDonkey
  • Start date Start date Jan 5, 2015

WonkeyDonkey

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#1
  • Jan 5, 2015
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OK, looking back through all the old header gasket topics I see lots of talk about using RTV in addition or as a substitute for the manufactured header gasket.
Question is which side do you put the RTV on? Are you putting it against the head and the gasket or the header flange and the gasket? Both?


With Stage 8 bolts do you put the retainers on after heat cycling them? Probably explained in the instructions, but I haven't even bought the bolts yet, just thinking about them as a way of fixing this leak.


FYI, stock heads, JBA shorties, the last owner replaced the gasket with a NAPA part and install was at the original dealership. Unfortunately that gasket only lasted 1500 miles, so I might be looking at getting the header flange machined.
 

srtthis

the guy doing it does every local racers rear end
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we put it on the header then put the header on. put 2 end bolts in to hold it in place then pull from the center out

you should be ok with black... we run copper now. the turbo makes to much heat and pressure so we switched from black to red then red to copper
 

WonkeyDonkey

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Cool. Thanks.
3 day weekend coming up...
 

7991LXnSHO

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Copper RTV was made to be the high temp exhaust gasket maker. Do not even think about another color got this spot. I will be looking at soft, aluminum gaskets next time. The header is most likely to have imperfections or not be flat, so that is the side I might seal.
 

WonkeyDonkey

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I was going to use copper, it's just as easy to find as the other ones. In the old threads one guy discussed using red, but copper suits me fine.

http://www.latemodelrestoration.com...-95-Mustang-50-58L-Extreme-Exhaust-Gasket-Kit
Looks like a lot more than I need for the stock motor, but it includes those locking bolts.
 

7991LXnSHO

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Never having to chase a loose header bolt would be nice. If you can afford it, go for it! I have thought about drilling and safety wiring the bolt heads next time, but this looks nicer!
 

mikestang63

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#7
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i've used stainless steel allen head bolts with lock washers from True Value or Home Depot. Cheaper and easier than Stage 8.
 
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srtthis

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7991LXnSHO said:
Copper RTV was made to be the high temp exhaust gasket maker. Do not even think about another color got this spot. I will be looking at soft, aluminum gaskets next time. The header is most likely to have imperfections or not be flat, so that is the side I might seal.
Click to expand...
we used black on the nitrous motor and never had an issue. the turbo motor just makes to much drive pressure and to much heat.
 

WonkeyDonkey

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7991LXnSHO said:
Never having to chase a loose header bolt would be nice. If you can afford it, go for it! I have thought about drilling and safety wiring the bolt heads next time, but this looks nicer!
Click to expand...


I just ordered these into the local store. Way cheaper than the other kit and the hard work of drilling for the safety wire has been done for me.

http://www.autozone.com/exhaust/exhaust-header-bolts/spectre-lock-wire-header-bolt/723229_0_0/
 

WonkeyDonkey

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mikestang63 said:
i've used stainless steel allen head bolts with lock washers from True Value or Home Depot. Cheaper and easier than Stage 8.
Click to expand...

Can you elaborate? Which type of lock washer? The ones with teeth or the split style?
 

srtthis

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i just use ARP and put a little RTV on the threads. they never back out
 

mikestang63

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WonkeyDonkey said:
Can you elaborate? Which type of lock washer? The ones with teeth or the split style?
Click to expand...

plain ole stainless steel split type lock washers. never have to worry about them coming loose. I'd go with a 1" bolt to give more to grab on to.
 

jrichker

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7991LXnSHO said:
Never having to chase a loose header bolt would be nice. If you can afford it, go for it! I have thought about drilling and safety wiring the bolt heads next time, but this looks nicer!
Click to expand...
In the days of my youth I was an aircraft mechanic, so I still do some things that way. The bolt heads were drilled with a #52 drill bit (about .040) using a drill press and lots of WD40 to cool the bit. The head is drilled with the holes in a cross pattern at 90 degree angles to each other.

The bolts are 3/8 -16 thread stainless steel Allen head, 7/8" or 3/4" long depending on the thickness of the header flange that is on your headers.

I bought a 5/16" Bondhus Balldriver Allen wrench, it works like a universal joint. You can tighten up the Allen head bolts at 15-20 degrees off center angle and still get everything tight. Cut the "L" part off the wrench with a cutoff wheel and stuck the straight part in a Allen socket. This works great, because the Allen heads are smaller than even the 12 point bolt heads, and with my fancy tool I can tighten them up with a torque wrench.

Torque the bolts down and pull off about 12" of .032 stainless steel safety wire. Thread the wire through 2 holes, or just one if the other one is blocked by the header pipe. Pull the wire through until the ends are even. Twist up about 2" with your handy-dandy safety wire twister pliers, making sure that the wire pulls the bolt tighter as it routes across the header pipe. Make sure the twist ends at the wire hole in the next bolt, and that it pulls the bolt in the tightening direction. Thread it through and twist up about 3/4"of wire on the other side of the hole and cut it off evenly. Fold it over about midway so that the sharp end doesn't stick you.

The safety wire takes about 10-15 minutes a header pipe to do right and make it look good. The driver's side is easy, but you have to remove the mass air & smog pump air plumbing on the passenger side to have room to work.

 
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WonkeyDonkey

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Hey guys, should I even put these back on?




They are 22+ year old JBA shorty headers (I mean, they need to go back on this is a DD not a project). Should I shop for new ones?
Do all headers have the seam at the flange/pipe? Should that get machined flat?
I am just going through the prep and cleaning them like crazy.
 

mikestang63

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#15
  • Jan 9, 2015
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WonkeyDonkey said:
Hey guys, should I even put these back on?




They are 22+ year old JBA shorty headers (I mean, they need to go back on this is a DD not a project). Should I shop for new ones?
Do all headers have the seam at the flange/pipe? Should that get machined flat?
I am just going through the prep and cleaning them like crazy.
Click to expand...

Unless they leak, spray them with some VHT high temp ceramic paint and slap them back on.
 
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WonkeyDonkey

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mikestang63 said:
Unless they leak, spray them with some VHT high temp ceramic paint and slap them back on.
Click to expand...

Cool thanks. I wish I had time for paint...plus, only getting the DS done today.

I was worried about the header flange not being glass smooth.
 

7991LXnSHO

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#17
  • Jan 11, 2015
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Smooth the raised ridges lightly with a fine, flat file then use the copper RTV on that side as stated. Unless one or more pipe flange is really receded from rust and exhsust, you should be good to go if the pipes are solid but ugly.
 
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