can I use lead to seal an exhaust leak>

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pishta

pishta

I know I'm right....
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I know it sounds funny, but lead can just pour into a void and harden up like...lead. It melts at a minimum 650F so it would need to get pretty hot down there to melt off? Heres the background story: My 35 year old Mazda B2000 had a muffler leak so I bought a new one and attemted to install it. It was a fully welded system so I had to cut and reweld the system. trouble is its near impossible to weld on top of an installed pipe, as well as on paper thin rusty exhaust pipe with a MIG or with slightly better results, a stick welder. So I got it welded back up and there are pinholes everywhere even afgter I ground down the birdshit welds of the MIG and stick welder. so I unbolt it (1 slip fit after the muffler) and try again to fill the pinholes and then blew a huge hole in the thin pipe. So Now I got a .38 sized hole in the side of the pipe at a 90 that I cant easily replace and come up with another idea to slip a larger piece over that patch job and weld that in. Im back to square one with welding that on as Ill blow more holes in it. So my idea was to slip a joint over the pinholes and back fill it with lead, holding the pipe vertical so it flows in. We did that with phone line splices years ago. There is no flexing on this joint. I doubt the pipe gets anywhere close to 650F even a foot after the cat.
 
Pishta what about cutting a piece of pipe in half slipping it over the hole than using these 2 at each end.
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Quit bein a cheap *** and put an exhaust system on it.

Even if the lead doesn't melt, the fumes alone from it could cause some unwanted results. Lead is some nasty stuff.
 
Rusty, tell that to an OLD telephone splicer. They used that stuff every day, sometimes in manholes, for years on end. Itll probably get professionally done but Id like to see if this could work.
 
pishta said:
Rusty, tell that to an OLD telephone splicer. They used that stuff every day, sometimes in manholes, for years on end. Itll probably get professionally done but Id like to see if this could work.
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Yeah well, that doesn't change anything now does it? People have done stupid **** since the beginning of time, but that doesn't make it right.
 
I think if I was in your shoes I would try and wrap sheet metal/ pipe around it and clamp that

What instantly came to mind you talking about lead was "old school" sealing cast iron sewer / drain pipe. "Oakum" and lead. Made a VERY interestin' smell. My gramps was doing this when I was maybe 5 years old. I can still conjur up the smell
 
All things health related aside, that seems like a pretty big hole to fill with lead. In my experience to get the lead to stick, the parent metal will have to be near red hot.

I'm thinking cut out the bad pipe, get a new piece of pipe with both ends flared and slip that over the old tube and use clamps like pictured above.
 
If you don't know how to tack fill a hole tack a patch over it, because lead is going to be a PIA and possibly even pour in and partially plug your pipe.
I also agree with YR in slipping a sleeve over both ands and clamping it, but I would probably use the U bolt style clamps since they have better crush for sealing.
 
yeah, probably wont work if I have to get everything glowing. Ill go with the long SS lap-joint band clamp , cut the system in half again and use some stick to seal the holes ( Flux MIG just craters, I can back stick hole with copper spatula to fill) and use air pressure and a bottle of soapy water to test for leaks. Jeez what a can of worms! I just read that lead wont stick to clean steel. Well, none of this stuff is clean. I think the muffler is "aluminized"
and the adapter is just straight slightly oiled exhaust pipe stock from a shop.
 
couldnt hurt, right? Thought it didnt take to heat well. Maybe Ultra copper 700F RTV?
 
pishta said:
couldnt hurt, right? Thought it didnt take to heat well. Maybe Ultra copper 700F RTV?
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Walker Acousti/Seal applied to the edges of the patch.

(Keep away from actual hole, within reason. It expands like Great Stuff (maybe not as much as Great Stuff does) when heated by exhaust and fills gaps, etc.)

It will mushroom out a little, and fill the gap between the patch and the pipe inward from the edges.

I had used it between head and cat on a late 80's VW. Heat is no problem for it.

RTV will rely on cleanliness and thoroughness to seal well. Acousti/Seal is way more forgiving.
 
Walker Acousti/Seal...Thats the stuff I was looking for! Have to give it a try.
 
I will give a short course in economics, since you seem to ignore post #3. When trying to be cheap, one will attempt to spend less. Money and time is spent going for patches, and application on a rusty paper thin system, in the end just as much will be spent. It will not last like like a new one, so the fix will continue. I speak from years of experience doing it wrong.
 
Cheap is a mission on this beater. I used VersaChem Muffler weld. Its like a gray paste, looks/acts just like JB going on. Turned to rock in 24 hours without heat. The system was not paper thin, only where I ground the weld to make it look pretty. Of course once you get a blow-through, its hard to start building with what took it down. Im totally satisfied with what I ended up with. Sealing pinholes with a stick or flux MIG is like killing gnats with a hammer. Replacing is a solution, but not this time.
 
Gnats ??? is this a hillbilly thing like claw dags ??? fill me in.
 
Gnats are tiny little flies that just hang around your head and buzz in your ears, get in your eyes and up your nose. Pesky little F'rs.
 
Up here they go by the name of no-see-ums, and during certain times of the year, are a way of life. It gets worse the further North we go.And then there are; sandflies and blackflies and fishflies, and of course the mosquitoes are as big as horseflies,lol.
 
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RustyRatRod said:
Quit bein a cheap *** and put an exhaust system on it.

Even if the lead doesn't melt, the fumes alone from it could cause some unwanted results. Lead is some nasty stuff.
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-----------------------------------------------Agree w/ this answer. I AIN`T EVEN GONNA READ THE REST OF THIS !
 
And we've been burning leaded gas for how long? Some of you old timers know what that was.....C8H20Pb.
 
pishta said:
And we've been burning leaded gas for how long? Some of you old timers know what that was.....C8H20Pb.
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Yeah but with a GOOD exhaust system, that goes out the tail pipe.
 
Ha, how about the guy in front of you in the drive through back in '74 with that big overlap cam and the pig rich Holley? This would have been far downstream of any temps higher than what would re-melt or even re-fume lead, and the dangerous fumes are actually produced when you vaporize it. It's a moot point now anyway as I have sealed it with some muffler seal.
 
At the end of the day,frustration at its peak,what is your time actually worth?
I run out of patience swatting mosquitoes,not to mention filling pinholes. Use a steel tig filler rod (read coat hanger) while tacking with the mig. It works but in the end its a waste of time.
I send the tubework to the local shop,they can bend and install cheaper than i buy ready made pipes. As mentioned,here in manitoba the winged biting insects can get nasty. Two hands for welding, none left for swatting.
 
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