Cracked exhaust manifold?
 

So yesterday when changing my thermostat I found a crack in my exhaust manifold. I knew these were prone to cracking and I suspected I had one because I can smell pure exhaust if I walk by the engine bay with the engine running. Can I wait till next spring to replace it? Is there a temporary fix that can last till spring? Should I just not worry about it.
Thanks

Looks like it was hit with something, they dont crack there. maybe weld it close

I also thought that it looked broken not cracked. I can't weld. Shop? How much do you think it could cost?

I can't imagine costing much, though the welder would have to be very careful with the fuel line that feeds the fuel rail - maybe use some sort of insulating wool like roxul insulation in between.

Maybe other members who weld can give better advice.

Yes it is an unusual spot to crack, What it looks like is someone used a pry bar between the exhaust manifold and that bracket (which looks bent up) and cracked the manifold.

I would remove that bracket, clean up the surface real well (no rust) and get someone to weld it, hit up your local jeep club for a member with a welder, or just take it in, should be $20-30 to weld up at a shop. (but hard to put a price on it depending on where you live and competition)

You think I can just leave it or is it a priority fix.

I'm sure you can get through a couple of winter months as is. I would have suggested someone touch it up with a mig, however, if it's weak (thin) there they may blow it out.

Just replace it when you can.

Have it welded & be done.

Talking to several automotive welding shops they said they refuse to weld thin wall headers because they've had too many come backs because the header cracked around their weld.


To get by until you can replace your header you might try using Blue Magic Xtreme QuickSteel to patch up the hole. Follow the instructions carefully.


Saw it available at O'Reilly Auto Parts.

If he's looking for a quick fix, it would be easier just to pull it off and replace it than to attempt to weld it. I weld a little, and I wouldn't attempt to weld that while it was on the Jeep. I'm sure it could be done, but I would rather not risk the damage to the components around it, and you'd get a better weld if it were on a table where you could reach it properly. If it has to come off anyway, might as well just replace it.

As for leaving it alone until spring, I wouldn't. Unless you can find some way to temporarily seal it off so that cold air isn't backing up in there in the winter, I would go ahead and replace it. Is your reluctance to replace it a money thing or a time thing? If it's money, just go get a cheap stock manifold from the junk yard to get you through until you can afford to replace the header. Pull a Part sells them for less than $30.

It's a money and time thing. I'm a high schooler with limited funds. My parents are reluctant to keep on dumping money into this thing for the moment. I guess I could throw a junk yard header on but I'm not sure my dad would let me. I also don't know if I could find the time to pull the intake and all the stuff on it off and put it all back on. I'll ask my local exhaust shop to see what they think anyway.

Also could this cause bad MPG? I drive my Jeep like its a mustang but I think I should be getting over 10-12 MPG mixed.

Possibly. If air is getting IN (during the off-cycle for that cylinder) it couild be making the O2 sensor report a lean condition, which would cause the PCM to dump fuel.

I suggest you try Ken's remedy. It will only cost a couple of bucks to try, and if it works, you are home free. Make sure you clean that area VERY well, and more than you think you need to. Wire brush then sandpaper. You want the metal shiny bright and rough.

If it doesn't work, well, it was only a few bucks to try it, and it can be cleaned off well enough for welding.

Another possibility: High school welding class? Maybe a free learning project? No welding class there? Try a local junior college. The worst they can do is laugh at you and call a press conference to mock you, right? ;)

Braze or weld. Absolutely NO Epoxy/Glue/JB Weld/MarineTex etc will work there. ever. It will melt off.

Id brush it, and braze it with some MAPP and silver rod. Would seal up enough till you get around to a new manifold.

x2 ^

Make sure that's even a crack in the first place. I bought a new dorman header about a week ago and it had he same looking little knick in it.