cracked rear exhaust pipe at Y

[horizonchaser]

thanks horizonchaser. i havent used the nickel spray powder. is this more like a bronzing technique or is it essentially a type of filler metal? are u still getting a bead- a complete melt of metal on each side of the crack and having them flow together for a true weld? has the nickel spray powder worked for u on a repair like this?

It is more of a filler material, and a pretty good one at that, depending on the application. It works wonders on sealing say, a cracked oil pan. Cracked sealed, but also no real stress on the pan. The terminal end of that pipe where the weld would be, would get some stress. Be it from daily driving, potholes, or whatever made it crack in the first place.
You would get a complete bead all the way around, and with added layers to build up the height & thickness if you like.
Like Glimmerman said "these repairs are marginal". If it were a crack in the bottom of an oi[ pan, it would last forever but given the area of the weld in the exhaust pipe, with the "heat cold cycles" on that pipe, the metal could be really fatigued. The life is out of it, as we say in the cast iron moulds that we deal with.

 

[Wayne R]

I also have an 02 Road King last year my pipe split at the Y, I can't weld, but I removed the exhaust and had a friend weld it and a year later and 5000 miles all is still good.

 

[Big D 2002 RK]

A buddy mig welded my y on 02 rk and my brothers 97 rk. We cleaned pipe really well,no problems. there may Y pipes available outthere from people who went to true duels.

 

[horizonchaser]

I also have an 02 Road King last year my pipe split at the Y, I can't weld, but I removed the exhaust and had a friend weld it and a year later and 5000 miles all is still good.

Glad to hear that worked out well for you. I still have my original cracked pipe in the garage and I believe you have just inspired me to take it into work and do a "Government Job" on it. I want to take before and after pictures of it and post it for all to see.

 

[oldscoolz]

lots of good info. wayneR, what kinda welder did ur buddy use? glimmerman, ur experience holds a lot of weight. i'll prep it up real good inside and out and pre heat the whole area cherryred before i put the weldin tip on and actually run the bead. i'm thinkin i'll OA torch weld it and keep an eye out for a cheap used pipe as a backup. i've still got some good ridin days here as far as the weather goes, but will pull it off and git er done when i get a cold/rainy weekend. i'll send some pics and followup when i finish. thanks everybody for the help.

 

[Wayne R]

right now I can't remember what method he used to weld it, I gave him the pipe and he brought it into work to do it, I do recall him saying something about the metal being a little different, but I'll try to find out and post back later.

 

[NEWHD74FAN]

S-6 contains a 6% silicone load to float out impurities. use an oxweld 65 and avoid hi-tensile stuff like ER70-S6. it is much stronger than the surrounding stteel and will most surely break. DO NOT BRAZE! this is soft bronze and does nothing. the crack will propogate (get longer) and then nothing can be done.

Definitely do not braze...! Bicycle frame welding vs brazing, no contest, brazing under high stress cracks and breaks, be it on road or mountain bike frames. Never tried exhaust tubing, usually poor metal quality used at the start...:56:

 

[glimmerman]

make sure this is very clean. if you have access to someone who can do a GOOD dye penetrant test of the area you might find more than 1 crack. occassionally there will be several parallel cracks in the same area. fixing 1 will not stop the rest. there may be cracks perpendicular (90*) to the crack showing. both are indicative of metal fatigue. there is a phenomenon called stress corrosion where the area looks like spider web cracks when using dye-pen. very common in steels and in particular in stainless steel. sorry for the metalurgical sermon, just trying to help. and don't overheat the area. gently preheat to about 350*F before you start and the coat hanger is probably the best filler wire. soft and flexible. weld about 1/4 in. past the crack at each end.

 

[horizonchaser]

lots of good info. wayneR, what kinda welder did ur buddy use? glimmerman, ur experience holds a lot of weight. i'll prep it up real good inside and out and pre heat the whole area cherryred before i put the weldin tip on and actually run the bead. i'm thinkin i'll OA torch weld it and keep an eye out for a cheap used pipe as a backup. i've still got some good ridin days here as far as the weather goes, but will pull it off and git er done when i get a cold/rainy weekend. i'll send some pics and followup when i finish. thanks everybody for the help.

Would definitely like to see pics. Although the welding job I wouldn't doubt. It is the longevity of the repair that interest me. Please keep us informed.

 

[oldscoolz]

thanks all. special thanks to glimmerman for the detail. did some bench testing yesterday on scrap tubing about the same thickness. looks like ive got the right size welding tip for the job. was able to run a nice bead without burnthrough. now need to go to welder supply and get the filler. beat me down, glimmer, but i'm not gonna use coathanger wire. i'd be willin to do that for other applications but i wanna give this the best chance to last for a while.