Removing headers

I have a HUGE crack in my header on my 95. It is on one of the two pipes that go into the collector. What do I need to remove to take out the pipes and have a buddy weld them?
Ben

Haven´t removed them on a 95. But have welded a few. All that I have welded, were an alloy, got some nickle or something in there. Yours may be some warped, lay the sealing surface on something flat. I´ve warped them some more welding. Used a wire welder, a little hotter than normal, put some spot welds across the crack before welding. Sprayer the header (with an old window pump sprayer filled with water) to keep the heat down. Welded in short runs, and allowed it to cool some between runs. Control the warpage.
Have spot welded them, while still in the vehicle, then removed to finish. (after unpluging the computer/why take the chance).
I´ve welded a lot of pipe, sometimes have to weld a little on this side then a little on the other side, kind of controlled warpage. Haven´t had to throw one away yet, but have them flex pretty good.
When reinstalling, tighten from the middle out, in stages. A very light coat of lithium grease on the gaskets or a very fine/light coat of high temp silicon. Will help them flex/slide a little during installation, if they are warped.
They usually cracked agian, next to the weld, not at the weld, after a few years. A trip to the oven (annealing) or a softer wire (maybe a soft stainless), might cure the temper cracking. Boat shops are good at repairing headers and often have an oven.

To take it out is pretty easy. Two hour job total to remove/install again. Remove the TB, all sensors need to be unplugged, take the ps pump off, and take the bolts off the manifold and header. Helps to have a extension on the socket. I just layed the manifold on top of the valve cover, remove the gasket and clean that area, be careful with the O2 sensor. Install in reverse. Pretty easy with the extensions and a good light.
Juice

I wouldn't bother welding unless money was really tight. They always seem to continue to crack once they start. I welded mine twice when it cracked. I built a quick jig to mount the exhaust manifold in while welding to control warpage. Worked good; first time it lasted around 25K and something like 20K the second time. When I rebuilt the motor I replaced the once again cracked manifold with Borla header - I wish I would have done that the first time! Good Luck

Woody

juicexj24 said:

To take it out is pretty easy. Two hour job total to remove/install again. Remove the TB, all sensors need to be unplugged, take the ps pump off, and take the bolts off the manifold and header. Helps to have a extension on the socket. I just layed the manifold on top of the valve cover, remove the gasket and clean that area, be careful with the O2 sensor. Install in reverse. Pretty easy with the extensions and a good light.
Juice

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You've got to be kidding right? Removing the exhaust manifold and re-installing the new one is an all day job the first time you do it.

Take my word for it, buy a wobble extension. You'll need it!

I can't wait to remove them. I better clear the weekend. BTW, what makes them crack? Is it from flexing or just crap metal?

Sometime in mid 89 they changed the stock header, it was almost twice as thick as the older one. Still seemed to be some of the thinner type in the parts system for years afterwords.
Have seen many crack after exhaust/muffler work, seems excessive use of the old BFH, on the exhaust system strains them some. As does using the exhaust system as a skid pan.
The older ones seem to be some harder than the newer ones, have always thought, heat and water splash may have hardened them and worked/flexed the headers in strange ways.
The thicker walled type, seem to last some longer.

Do I have to do anything with the fuel lines? Do they all stay intact?

you don't have to remove the TB and such, just unbolt the intake and set it off to the side, remove your PS pump and airbox, the rest is simple. don't make more work out of it than it needs to be.

Disco the fuel line, vacuum lines, TB cables and injector wiring and the manifold comes completely out without removing the fuel rail or injectors.

Crow's foot works too if you don't have a wobble extension.

XJack said:

Disco the fuel line, vacuum lines, TB cables and injector wiring and the manifold comes completely out without removing the fuel rail or injectors.

Crow's foot works too if you don't have a wobble extension.

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I had my 89 manifold welded up once, lasted about 3 years, the 2nd time it was cracked even worse. Stainless steel becomes very brittle when heated and cooled a several 100,000 times..........which is why the manifolds crack as they age.

The fuel lines use a quick disconnect coupler that consists of 2 O-rings, a spacer and a plastic retentions clip that often breaks with age. Plan on having at least one of these available to reassemble if this occurs........dealer only, about $9.00 bucks :wow: with my dealer discount.
The injector harness needed to be unplugged on my 89, carefully remove the square wire spring retention clips and unplug each injector plug. Do not remove the fuel rail from the injectors or you've just created more work and possibly more $$ in parts if you cause an injector o-ring to leak.........not to mention the potential for an engine :flame: ..........check all fuel fittings immediately after startup following reassembly.........had a buddy BBQ his XJ to smoldering puddle in the road, due to a leaky fuel fitting.

Good clarification XJEEPER. Probably should have said why I didn't want to remove the fuel rail or injectors.