Hi! I just bought a 96 Accord EX with a cracked exhaust manifold. Relax, I knew what I was getting in to.

I can do this the "right" way, but half the fun in buying cheap dailies (for me, at least) is novel shortcuts. I could get a used manifold from the pick-n-pull for $65, or order a new "ebay" one for $70 shipped (vs the two unsolicited quotes from mechanics in the $450 range), but I think I can do better .

So! I took a trip to Autozone, and got some JB weld FOR $6.58. The back of the package makes some hand-wavey warnings about FOR THE LOVE OF ALL THAT IS GOOD AND HOLY DO NOT USE ON SURFACES OVER 600'F. That's so cute. Good thing only women pay attention to directions.

This is where you come in, fellow car nuts. What's my worst-case failure mode? The worst I can think is that the heat dissolves the compound and flakes of it end up fouling my catalytic converter. Medium case: It cracks but stays put, and I just have to replace the whole thing. Best case: the seal outlasts the heat death of the universe (but it probably won't make it past Sol's red giant stage).

Questions? Comments? Confirmation? Is this a Bad Idea ?


UPDATE: Permanent solution is discussed here.

 

I highly doubt the exhaust will go over 600* or you will be having other problems lol

I say go ahead and try it.. why not..

 

Personal experience with JB weld, used at the end of the exhaust manifold, just before the converter. The JB weld held up fine for 3 days (i was a delivery guy at the time, so... 3 days for me would be the equivalent of 2 or 3 weeks of driving for another person).
After that, the "weld" was cooked, and just cracked... and eventually fell off on its own. I used it 3 or 4 times for about a week then just got me a new gasket (that's what i was using the jb weld for).
Good luck.

 

Uhh, exhaust gases out of combustion chamber are usually double that.

I thought JB Weld is an aluminum based epoxy compound. AL melts around 1200*F soo...

 

Yeah, I was thinking the exhaust gases do get hotter than the rating. I was mainly asking if "we" expected damage to the cat from melted JB Weld.

 

There are different kinds of aluminum, some can melt with 1/4 of the temperature you mentioned.

As to answer the question, once again. This is a fix for a few days or so, eventually you will need a more reliable repair. Because it shouldn't melt, there won't be damages to the cat.

 

well you taught me something today my good sir.

 

Exhaust manifolds for 4cyls here in my local pick and pull are 15 dollars and the accords are a dime a dozen

 

Ah yes, the ole right way or wrong way debate. I find myself in this dilemma more often than I want to lately.

And I agree, directions are overrated haha! But in all seriousness, I don't think the duct tape of the car world (JB weld) will save you here...

This is true. That local mechanic was trying to pull a fast one on you. 400+ for a stock mani? Good one.

But yeah, I wouldn't try that on the manifold. My friend has used it to seal up cracks in his oil pan on his Jetta (anyone who has a volkwagen knows why this happens... especially if its lowered) and its worked fine. That quite the temperature difference though.

 

I had this EXACT problem, a cracked (ebay) exhaust manifold. I didn't want to pay to have it welded so I bought some JB weld. I let it sit over night and after driving for about 15-20 minutes, opened the hood and saw the exhaust sputtering out of the crack and the jb weld burned and brown. It didn't work. I had it welded.

 

$40 for a new stainless steel one shipped from ebay

Then you have bling

 

, consult a local welding shop for a price unless its more than the ebay option.

 

Yeah, that's worth a shot. There's one around the corner from me.

 

On a side note, here, there's another option.

One of the first things I looked around for was a set of headers for the F22B1. Most of what I found was the long-tube kind, where there's a two-piece header that replaces the cat.

Can anyone recommend a cheap shorty header that would drop in right here the existing manifold is with the same connections?

 

.....

 

I've seen the ebay ones (and never $40 shipped), but if I can get a OEM replacement for 70 or a better-flowing shorty for, say, $100, I'm all ears.

 

Maybe the prices went up - the one on my H22A was like $40 shipped to my door, thing too a beating too and held up.

I can't access eBay at work, I'll see if I still have that vendor in my profile. It was one of the DC Sport replica headers.

 

Thanks, you rock!

 

Progress report!

I got some high-temp compound in, and have applied it. It's curing right now. I'll let you guys know what happens. In the mean time, if you have some recommendations for a shorty header (that is, one that will mate directly to the down pipe that houses the cat), let me know!

Before:


After:

 

I think what you are confusing for a cat is just the down pipe, which has a heat shield attached to it. AFAIK all '94-'97 F22B1 coupes/sedans use the same exhaust. Majestic Honda Link.

From the head the exhaust goes;Manifold>down-pipe>'flex' coupling>cat>mid-pipe(resonator)>tail(muffler) section.
It would not be good for engine oil longevity to have such a component directly underneath the oil pan. Can you get an under shot of the car? There are slight differences between '94/'95 and '96/'97 but the only difference I believe there is with the '96/'97 OBDII exhaust is a secondary O2 sensor after the cat. Any header for a '94-97 F22B1 should fit your car.

FWIW, JB Weld is rated 600*F and JB KWIK is rated 300*F

 

ghetto-tech ftw!!!

good luck

 

For what it's worth, I used JB Weld on a rocker arm in the head. 6 years and counting and it's still good to go.

 

UPDATE

So, the epoxy solution only held for a few weeks. Here is a closeup:









I bit the bullet and bought an eBay header for $75 shipped. This post was very helpful, as the box came sans instructions.


Here we are starting to bronze after the idling leak check and a slow test drive:


Here we are after winding it out a few times to check pressure:



It seems to be holding up. There's a neat rushing whistle sound once you hit VTEC, similar to a turbo. I don't know if that's just better flow, thinner walls of steel, or a leak. I assume if something was loose, though, I'd have more noise from the secondary vibrations. The link I posted above is correct: remove both the extra bolted hanger on the back and front of the block. They will just get in your way. The install took way longer than it should have. It took about 4.5 hours, but were I to do it again, I think we could do it in 2.5 . If you have access to a lift (you probably aren't reading this), it would take even less time, as you don't have to do everything in the space of four jackstands.