97 TJ Exhaust manifold replaced
 

My manifold was cracked when I bought the TJ last year. It wasn't too bad,
so I just kept an eye on it.

About two weeks ago I was checking it and one of the two downtubes was
cracked nearly all the way around.

I had been thinking about getting a header. A good one like a Borla.
Well, this was on a Saturday when I found it getting so much worse and I
really wanted to get it fixed same day. I'm a pretty good welder and I
thought about just welding it up.
I'd heard that many folks had done this, most with it just cracking again
later on.

Then I thought...I'll get on the net and see what AutoZone has. They had the
header in stock!, right here in my town. I was impressed. I guess so many
have failed they chose to stock up on them. It was $191. So I decided to run
take a look at it.

It was beautiful. Made in China and all. Stainless steel !! all but the
flange.
(Checked with a magnet), and it was pretty obvious visually.
The flange was very straight and smooth. Tig welded !! And a good job too.
(I was an aircraft mechanic, and pretty good at visually inspecting welds)

The original header was carbon steel throughout. It was mig welded. Looked
like it was welded in a junior high welding class. It was horrible. I'm
amazed it held together as long as it did.

The construction as far as design, was an exact copy of the original. Only
the materials and craftsmanship were far better.

Two weeks now and I'm still running good and a lot quieter.
Time will tell, but right now it looks like a made a good call.

Just wanted to let everyone know.

Mark

Re: 97 TJ Exhaust manifold replaced
 

Mark Burns writes:

> The construction as far as design, was an exact copy of the original.
> Only the materials and craftsmanship were far better.
>
> Two weeks now and I'm still running good and a lot quieter.
> Time will tell, but right now it looks like a made a good call.
>

Thanks for the story.

But isn't the old design flawed? I thought you needed some kind of
redesign with accordion flex coupling to take up thermal expansion?
Shouldn't this replacement just fail the same way eventually?

Re: 97 TJ Exhaust manifold replaced
 

I failed to mention that the new one does have the accordion flex couplings.
I said "exact copy" which was wrong.
When I wrote the post I had forgotten about them.

I'm sure they will help some, but I think the better materials and welding
will help more.
The flex couplings are a long way from where it cracked.

Mark





"Richard J Kinch" <nobody@nowhere.com> wrote in message
news:Xns93C8CDCD98BBsomeconundrum@206.127.4.11...
> Mark Burns writes:
>
> > The construction as far as design, was an exact copy of the original.
> > Only the materials and craftsmanship were far better.
> >
> > Two weeks now and I'm still running good and a lot quieter.
> > Time will tell, but right now it looks like a made a good call.
> >
>
> Thanks for the story.
>
> But isn't the old design flawed? I thought you needed some kind of
> redesign with accordion flex coupling to take up thermal expansion?
> Shouldn't this replacement just fail the same way eventually?