Topic: can I braze closed a hole in my HM341 pipe?

[Hondawggie]

I have been warned that perhaps a regular welding job will overheat and melt the 'good' parts of the HM341.

Here are pics of the hole and crack, right where the header pipe slips into and is welded to the muffler section, on the bottom of the pipe -- looks like Honda knows water collects there as they came with 2 holes in the vicinity:

Can I use a brazing approach here, or what is the best way to patch this?
I have an RD400 with chambers that had a leak and brazing was used to patch the chambers and it seems to work.  Not sure if the HM341 metal will take to brazing though?






EDIT:  the rest of the pipe is solid, chrome is great, no dents, dings or scratches.

[TwoTired]

I brazed patches onto a Cb550 Honda pipe many years ago and they are still holding pressure.  The chrome does discolor in the heated area, though.

[lucky]

It is  steel.
 It will braze without any problems if you have the skill and know how to adjust your torch flame for brazing. You may need to put a patch over the hole if it is too large of a hole.

That looks like a lot of brazing though.
You cannot braze or weld rusty metal . It must me clean shiny metal.
To save the looks of the pipes I would see if there is some type of epoxy that could do the job.

FIRST though you need to STOP THE RUSTING. Use phosphoric acid on it  to stop the rust.

Check the that area of all of your exhaust tubes.

[Hondawggie]

Okay -- I'm going to have to have someone do this -- I have no welding tools, skills or experience -- the patched-with-brazing RD400 chambers came that way when I bought the RD last summer. 

I'm glad to hear I can bring these back on-line with brazing, thanks guys.

I've never used one but I'm wondering if a muffler shop would be able to braze.
I don't know what kind of repair techniques a muffler shop uses, but I'm thinking I should call a couple places to see if they could do this.  A muffler shop that specializes in bike mufflers in San Jose, CA would be cool, not sure if they even exist though.

EDIT: on the phosphoric acid to stop the rust prior to repair, I think Naval Jelly is phosphoric acid, isn't it? May have some of that somewhere.

[lucky]

You know the perfect place to get this repaired?

The local junior college welding school !!!

Ask one of the instructors if they could repair it as a class project.
Offer to pay something for it. Schools need money for supplies
Make sure to tell the instructor that they are rare and valuable parts. He will put his
best students on the job.
Classes like real life projects.

The beginning students spend their first semester with oxy-fuel welding and brazing projects.

[lucky]

Okay -- I'm going to have to have someone do this -- I have no welding tools, skills or experience -- the patched-with-brazing RD400 chambers came that way when I bought the RD last summer. 

I'm glad to hear I can bring these back on-line with brazing, thanks guys.

I've never used one but I'm wondering if a muffler shop would be able to braze.
I don't know what kind of repair techniques a muffler shop uses, but I'm thinking I should call a couple places to see if they could do this.  A muffler shop that specializes in bike mufflers in San Jose, CA would be cool, not sure if they even exist though.

EDIT: on the phosphoric acid to stop the rust prior to repair, I think Naval Jelly is phosphoric acid, isn't it? May have some of that somewhere.

Naval jelly will not work. It is tannic acid and is not the right kind of acid for this project. Read the package of naval jelly and you well see what I mean.
Phosphoric acid is very easy to get at most big box stores in the paint dept.
It may be called some kind of paint prep but just read the ingredients.

You can also get it at a West Marine store it is called metal prep.

Matter of fact I went into Home Depot and asked the paint dept. person for phosphoric acid and she said they did not have it. I walked right over to the shelf saw the green liquid called something paint prep and it said it was phosphoric acid.
Many $8.00 employees in welding stores and paint stores now know very little about anything.

I even asked one woman clerk at a big box store if she liked learning about all the hardware items etc., and she said NO that she was not interested.

[lucky]

The best way to do that job is to cut along the edges of the metal with a cutoff wheel (not cutting too deep) ,because it could have more than one layer.

Make cuts so that you can get rid of the rust part and be able to weld in a patch that is square or rectangular.

The thing is, is that it is better to have a neatly welded in patch and save a $1200.
set of exhausts than to just cover the rust  up with epoxy.

It can be oxy-fuel weld in addition to being brazed.
Muffler shops almost all only do mig welding now. The old timer muffler shop people would know how though.

Radiator shops are VERY good at brazing on patches.

[Stev-o]

Muffler shop should be able to fix that.

[lucky]

Muffler shop should be able to fix that.

Better hope they do not mig weld it.
 It will look awful and only be fit to be underneath a truck.

[Stev-o]

Dont you think a muffler shop can braze? And you suggest a jr college?

What are you smoking?

[lucky]

Dont you think a muffler shop can braze? And you suggest a jr college?

What are you smoking?

I think there may be some muffler shops that can still braze and have know how, but many muffler shops now just do mig welding. Put on new parts. They do not weld or braze old rusty mufflers. They just advise the owner of the vehicle that they need a new muffler. Muffler shops do not want to try to weld rusty old metal at all.

Many people THINK they can go to a muffler shop and get someone to patch up a rusty old muffler or exhaust, but I do not know any muffler shops that would do such a thing.

Maybe in a small town with very poor people.

If you live in a small town you chances may be better because in small towns the mechanics usually have to have more skills.

I was just alerting the OP that not ALL muffler shops know how to braze.

I have been a welder most of my life and many ,many times people ask welders to repair a leaking exhaust. Most welders just tell the person to go to a muffler shop where they have a lift and can fix the vehicle properly by putting on new exhausts.