Topic: ¿How about a new way to fix exhaust holes?

[Raul CB750K1]

I have recently bought another 27-year-old bike with 10.400 km on the clock. Everything original, including a rusted-through left pipe.

This Sanglas bike -spanish made- is in pristine condition. The pipes are simply unavailable anymore. Fortunately, the hole is facing downwards, towards the end of the muffler, so hard to spot from above -actually, I didn't notice it the first time though I laid down to check for rust holes underneath.

After removing it and vigorously shaking out all the flakes, and drilling out the rusted shield bolts, I was considering different options to repair it. I have seen welded patches, and I don't like them. Muffler tapes doesn't seem well suited for bike exhaust. I was thinking about using a piece of aluminum sheet from a soda can, to glue it into place -as I said, it is towards the end, so it really doesn't get THAT hot. Actually, the aluminum from the can "can" be polished, therefore it would be harder to notice. While I was brainstorming, I was thinking I could even cover the patch with sticky aluminum foil.

And that's when it dawned on me that I have used aluminum foil in furnace chimney junctions, and the glue seems to stick very well even when hot. How about simply covering the rust holes with aluminum foil? Two or three layers could give added strenght, or even using the soda can for strength and then using the aluminum foil for adhesive?

[nickjtc]

Do it, and send pics 'before' and 'after', Raul.

[troppo]

yep, i agree go for it and dont forget to take the camera

[Raul CB750K1]

Do it, and send pics 'before' and 'after', Raul.

I guess that your encouragement means "I haven't the foggiest whether it will work, but can't see why it won't. If it does don't forget to let us know...."   

[troppo]

I guess that your encouragement means "I haven't the foggiest whether it will work, but can't see why it won't. If it does don't forget to let us know...."   

basicaly yes lol
just wondering how thick this adhesive/tape is, but it would be a damned good easy fix for guys that arent looking for the "perfect" repeir

[mystic_1]

Doubting that furnace tape would stand up to the heat and pressure, both of which are far higher than on a furnace.  Pressure would probably be a problem before heat, the tape will get blown off the hole.

If it were THAT easy, everyone would be doing it already

mystic_1

[Jonesy]

I did just that with my old mufflers. I just backed them up with a bit of JB Weld, but aside from that one difference, I did exactly as you described with the foil tape.

[mlinder]

I tried JBweld and some form of metal sheet for the holes on my old BMW. Blew them out within a couple of days. Also, soda cans actually burn through and turn very brittle with extended exposure to high heat.

We're going to try some of this:
http://www.aluminumrepair.com/

On a friends c350's 4 into 4 pipes that have a bit of deterioration.

[troppo]

maybe some stainless glued on with jb weld and a couple of the smallest rivets you can find.
If you could find some way of getting the patch on the inside it would look better

[Raul CB750K1]

I did just that with my old mufflers. I just backed them up with a bit of JB Weld, but aside from that one difference, I did exactly as you described with the foil tape.

And what happened? I guess it didn't work or you should have already posted about it before.

[NickC]

Most auto parts stores carry muffler patch and pipe wrapping material, don't know how well it works though

[Gordon]

I tried the aluminum tape on my 550 muffler a couple of times.  It only held up for a couple of rides.  I tried JB weld, too, but it wasn't viscous enough to stay put in the hole long enough to cure.  I finally bought a tube of muffler patch, smeared some into the hole, and it's held up for almost a year. 

[kghost]

I dunno Raul.....but those spanish question marks are messing with me.

[mystic_1]

Most auto parts stores carry muffler patch and pipe wrapping material, don't know how well it works though

I patched a 2 inch hole in the front of the muffler of a CB750C (just aft of the headpipe joint) with a steel plate, "glued" with muffler patch putty and wired into place with stainless wire.  Once that set up I covered the while thing with muffler putty, effectively creating a wire-reinforced cast.  Looked great initially but the putty dried out and disintegrated after being run several times.  To be fair the last time it was run, the guy I sold it to had overheated it badly enough to discolor the clear on the engine, and melt the plastic dipstick  , but I think the patch job was already on it's way south before that happened. 

Welding would be the only "real" fix in this case, I believe.

mystic_1

[Jonesy]

I did just that with my old mufflers. I just backed them up with a bit of JB Weld, but aside from that one difference, I did exactly as you described with the foil tape.

And what happened? I guess it didn't work or you should have already posted about it before.

Sorry.. I didn't realize I was harboring such a critical secret! 

It worked fine. Granted it was for smaller holes, about the size of a pencil. For large holes, (like on my wife's 550), I cut out a section of clothes dryer duct, which is aluminum. I bent it to the contour of the muffler and scuffed the backside with sandpaper, as well as the area around the hole. I coated the entire backside of the aluminum patch with JB Weld and placed it over the hole and I then bound the whole works up with duct tape for 24 hours to let the JB Weld cure. After it cured I removed the tape, and it was good to go. It's lasted 2 years so far and has held up very well. The dryer duct is made from smooth aluminum which can be easily polished.

Most auto parts stores carry muffler patch and pipe wrapping material, don't know how well it works though

I tried that at first with the 550 mufflers before I went to the dryer duct. The tape would blow out after just one short ride.

[Blueridgerunner]

Melted the plastic dipstick  

[mystic_1]

Melted the plastic dipstick  

I know, I was impressed too!    Needless to say he's now cracking open the engine to retrieve said dipstick and survey the damage.  He says he think he found most of the dipstick in the oil pump housing.


mystic_1

[seaweb11]

There are some photos here of how I did one.  http://forums.sohc4.net/index.php?topic=19705.30

[Dave-and-his-550]

My 550 has a hole on the muffler the size of a golf ball. And, its rusting in other places where I'm worried its getting thin. I'd love to try something to patch mine sometime! I'm gonna take off my exhaust maybe today if it doesn't rain, and hopefully get as much surface rust off as I can. Will be using Kleanstrips Rust Remover. Works GREAT so far on everything else I've used it on.

I think this thread will come in handy down the road if I repair that hole, bookmarking now