Bike went BOOM! (and then my pants caught on fire...)

[BF06FLHTCUI]

I've been fighting an intermittent exhaust rattle for about six months, and over the last month, I've noticed a gradual increase in backfiring. So, today, I'm on the way home from work, had to roll it on (bleep bleep cagers...) and a really nice blue flame shot out from under the seat. Nice black char mark on my pants. I was going to post here and ask what would cause it, then i found a beautiful rusted/rotted crack in the splitter off the rear head. Now that I know what caused the problem, can anyone tell me:
What would cause the problem/rusting
How much of a pain is it going to be to back the exhaust bolts out, given that they are prob rusted too
If anyone has a header pipe they would be willing to sell for a reasonable price, because they have it laying around after replacing thiers with some fancy aftermarket piece.
Much obliged. Pic attached.

 

[Jack Klarich]

I've been fighting an intermittent exhaust rattle for about six months, and over the last month, I've noticed a gradual increase in backfiring. So, today, I'm on the way home from work, had to roll it on (bleep bleep cagers...) and a really nice blue flame shot out from under the seat. Nice black char mark on my pants. I was going to post here and ask what would cause it, then i found a beautiful rusted/rotted crack in the splitter off the rear head. Now that I know what caused the problem, can anyone tell me:
What would cause the problem/rusting
How much of a pain is it going to be to back the exhaust bolts out, given that they are prob rusted too
If anyone has a header pipe they would be willing to sell for a reasonable price, because they have it laying around after replacing thiers with some fancy aftermarket piece.
Much obliged. Pic attached.

First off, start squirting the nuts down with some PB Blaster, let it soak over night. If you have a heat gun use it, try not to use an open flame, if the studs back out throw them out and replace them, final torque on exhaust nuts is 10 ft lbs Cracking rear head pipes is usually due to a broken rear mount, the rear mount on older baggers was mounted to the starter

 

[dolt]

Very common occurrence in the early models. That split is subject to stress and if the pipes are mounted in such a way to add to that stress, everntually the pipe will split. The rear motor mount on early baggers is at the swing arm; the swing arm bolt runs through the transmission case which is attached to the engine case.

I have a complete set of header pipes and SE mufflers from a 2002 FLHT that will fit your bike. They are not pristine but in very good condition. I would be willing to let the pipes/heatshields go sans mufflers; PM me if interested, I have pictures I can send.

A couple of things you should address though; the backfiring issue should be resolved and you should have the engine/chassis alignment checked before you install another set of pipes.

 

[BF06FLHTCUI]

Thanks for the fast replies. Another quick question: What constitutes "older" and "early"? It's an 04 Injected Road King.

Thanks for the offer on the pipes. don't really care what they look like. Really only need the header piece, I have the Screamin Eagle IIs on there, sound REAL nice.

Hrm...thinking out loud here, I had a new rear tire put on not long ago, could something have gotten misaligned when the back end was put back togather?

Now, for what i am sure is a dumb question. Any way that I can patch or otherwise fix the crack? I ship out to Afghanistan right after the new year. If i can make it last until then somehow, ill live with it and add a new exhaust to the overhaul when i get home (complete top end rebuild, head gaskets, and shifter pawl replacement/centering pin leak fix)

 

[SirDimsdale]

Worth a try. Remove the pipe, clean it up and fill the crack with JB Weld. you can get at home depot.

 

[Adamal47]

Worth a try. Remove the pipe, clean it up and fill the crack with JB Weld. you can get at home depot.

JB Weld can't withstand that kind of heat. There is a exhaust repair putty
That I have seen at pep boys for roughly $10.

 

[Iceman24]

I'd get it off & take to nearest metal/welding shop...the hole doesn't look too big & they can probably fill, or tack on a plug to get you buy. It;s covered by heat shield so nothing's visible. Good luck!

 

[BUBBIE]

I am retired welder (shop owner).

Like Ice said, Me adding to it.

Pipes OFF the Bike: Find a welding repair shop that has S-6 wire in a .024 or .030 solid wire using gas shield. (argon blend prefered)

Weld the crack and IF you want an excellent job, they can make a small gusset (partial pipe piece) heated and formed over (neatly) the cracked area that has been repaired welded, combining the support there on Both the pipes at the "Y" and it shoulld last for Years More.

JMO

signed....BUBBIE

 

[BF06FLHTCUI]

Just a fast update. Got the heat shield on that side off. It is beyond repair it looks like. Appears that the entire weld joining the Y splitter off the rear head to the left side down pipe split, only the rest of the mounts and what not were even holding it that close together. Got a couple of quotes for used stock header pipe assembly for "about $100". Good price?

 

[BUBBIE]

Just a fast update. Got the heat shield on that side off. It is beyond repair it looks like. Appears that the entire weld joining the Y splitter off the rear head to the left side down pipe split, only the rest of the mounts and what not were even holding it that close together. Got a couple of quotes for used stock header pipe assembly for "about $100". Good price?

I'd say so...:53:

Put that puppy together and be OFF with the rides.

signed....BUBBIE