Welding exhaust pipe

[amaurer]

I cracked my exhaust pipe about an inch after the manifold and tried repairing it today. I cut out the cracked section and slid on a coupler and then overlap welded it at each end. Or, rather, I think I did... I'm not much of a welder; I took a single 30 minute welding class 2 years ago, and have only a 90A flux-core welder.

Anyway, I just kinda... did it... and then ground off the boogers. Basically I welded until it looked like there was good penetration on the inside of the pipe then filled it with water to check for leaks and rewelded any bits that were leaking.

Do you suppose this is gonna hold up?

 

[kurtnkegger]

The plus side, is there is a big hole on the end where the air is supposed to come out. I presonally wouldn't worry too much about pin holes. If you think you got good enough penetration to keep the steel in one piece, and it does...that is very important. A lot of guys when they weld try to move out of the "puddle" too quickly. There is a thin line with thin gauge steel, but if you turn down the amps a little, you can acheive a pretty decent weld on thin pipe.

 

[Joe Egolf]

Hey Drew, My tail pipe was hitting on the spring shackle and it broke and cracked.As you probably know there is no toyota replacement part available. My buddy and i finally cleaned up the break and welded a 4 inch piece of curved to fit piece of exhaust pipe on/over and it is still going.Almost a c clamp welded on if you will? I will check it tomorrow ,it all started with a broken hanger.

 

[Joe Egolf]

did it rust out or did it fail due to 3B vibrations

 

[amaurer]

This was actually on my BJ73, but I posted here cuz the traffic is higher. Still a 3B though. We landed the rockers on a rock, which pushes the exhaust upward at the manifold - the pipe kinda "telescoped" inside itself and cracked.

I guess the vibes are what I'm worried about... will a flux-core-welded joint hold up to a rattle-y diesel?

 

[Pin_Head]

It doesn't matter what you welded it with. It matters how it is welded. You can make a bad weld with any process. Muffler tubing is pretty forgiving of bad welds.

 

[amaurer]

It doesn't matter what you welded it with. It matters how it is welded. You can make a bad weld with any process. Muffler tubing is pretty forgiving of bad welds.

Hmm, ok. I wish I'd taken some of the inside of the tube so someone can tell me if the welds were bad or not.

Here's a shot of the outside. Survived the first trip ok, so thats something.

 

[kurtnkegger]

I don't see what you're worried about. Looks like your scab overlaps plenty, and after the grinding, doesn't look like there is any visible worries (I've seen plenty of grind jobs on bad welds). That weld might outlast you.

When you looked inside...Did the steel have a blueish color? Typically, when there is decent penetration, the steel tends to "blue", and with thin gauge steel, you will usually see a a 'blister' on the inside where your initial bead went. You get the blister right before the weld burns through...can't get much better penetration. If you saw any of that on the inside, you're alright.

 

[skidplate]

No worries! That looks good. Just think, you're that much more experienced now at welding.