Exploding Muffler

[Darky]

That sounds like mine, light rust coming through the hood and roof, worn through on the door. And yours did it with 200-200k on it, mine only claims 127k...But the truck is fun to drive, and really, at 40 years old, I'm not hugely worried about miles.

 

[Darky]

The aftermath...I cut both pipes just ahead of the muffler so at least backpressure will be even between the two sides.

The damage

The booger welds to save a few bucks on exhaust hangers...


The ruckus - click for video

If I could get it to sound like this without as much volume, I'd be set...sounds wicked!

 

[Skwerly]

LOL! That thing sounds like it's ready for Pomona!

 

[David_Bricker]

Yeah, you could have fixed it with duct tape - a LOT of duct tape!! :laugh:

David Bricker / SYR

 

[Yamadevil]

I would defiantly get muffler on that thing you need some back pressure but at least for the time being run a pipe further away from the cab or you might get sleepy

 

[Darky]

I want to try and figure out what the problem is before I put another muffler on and let it explode...

I've been told that raw fuel in the exhaust is the likely culprit. Causes have been suggested as either bad carburetor jetting, need to thin out the jetting a bit; or bad ignition in one or more cylinders allowing for raw fuel to be expelled from the cylinder. I will probably buy a new cap and rotor and ignition coil (already did plugs and wires when the new carb was put in) and see about getting my carb rejetted.

 

[91XJRubicXD]

That's not an explosion. That muffler was holding together with nothing and finally dropped out. The rust inside alone is a clear indication of it's age

Sent from my Samsung Infuse 4G

 

[Darky]

You obviously weren't in the truck with me to hear the explosion and see the orange flash in the outside rearview mirror...nor are you looking closely enough at the pictures to see the burn marks at each end of the muffler. Not to mention, in CA, rust really doesn't make that big a factor...look at the other muffler, it's looking weak, but it's not rusted to the point of falling apart.

Last thing, you need to turn off the tap a talk signature, it's actually a violation forum rules.

 

[Skwerly]

I have to agree, here. I can clearly see that the inner and outer steel of the muffler actually changed shape when it exploded.

[FONT=&quot]I wonder if this isn’t a case of that muffler becoming so fouled up and clogged it just let go. I have run some real, real rich mixtures in my time and never had a muffler go pop. I always run glasspacks, though. [/FONT]

 

[GSequoia]

I want to try and figure out what the problem is before I put another muffler on and let it explode...

I've been told that raw fuel in the exhaust is the likely culprit. Causes have been suggested as either bad carburetor jetting, need to thin out the jetting a bit; or bad ignition in one or more cylinders allowing for raw fuel to be expelled from the cylinder. I will probably buy a new cap and rotor and ignition coil (already did plugs and wires when the new carb was put in) and see about getting my carb rejetted.

Autolite 2100 would fix your problems


I'd consider jetting it smart. Get the exhaust buttoned up and find somebody with a sniffer.

 

[Darky]

I have to agree, here. I can clearly see that the inner and outer steel of the muffler actually changed shape when it exploded.

[FONT=&quot]I wonder if this isn’t a case of that muffler becoming so fouled up and clogged it just let go. I have run some real, real rich mixtures in my time and never had a muffler go pop. I always run glasspacks, though. [/FONT]

That actually had crossed my mind. When it went, the engine was bucking real bad and then POP and the engine smoothed. It mostly did it while under load, so I was thinking maybe excessive back pressure was screwing with the engine and it relieved itself by popping the muffler. But, yesterday, with no exhaust practically, it started bucking again, and at lower rpms than before. I had to turn it around and take it back home. So, I don't know anymore. It smells plenty rich outside so I figure at the very least, I'm burning/dumping more fuel than I need to at this level of build and might be able to even improve mileage and driveability hopefully with a better A/F mixture. :dunno:

Autolite 2100 would fix your problems


I'd consider jetting it smart. Get the exhaust buttoned up and find somebody with a sniffer.

By jetting it smart and getting someone with a sniffer, you mean taking it to a shop to be done properly? English man! This is my first experience with trying to get a carb setup properly. I was seriously considering taking it in to a shop to make sure it's done right.

 

[GSequoia]

I was seriously considering taking it in to a shop to make sure it's done right.

More or less a shop will do it, or if you have a friend with a sniffer (not too likely).

Another more home brew option is to weld in a couple O2 sensor bungs and read them to see if it's rich or lean.

 

[SC Rednek]

I'd guess misfiring. Get a timing gun and check the timing at idle and at high rpm to make sure it's advancing right, check the vacuum system for leaks if it isn't advancing far enough at high rpm. You should be able to find the correct advance for that engine published somewhere.

Double check all your plugs and wires too, pull the plugs and make sure one of them isn't fouled up from leaking rings or something, even though they're new.

If it was just running rich it wouldn't be "bucking", and I didn't see any smoke coming out the exhuast in your video. And there's no way you did that from back pressure caused by a plugged up muffler.

 

[Darky]

I'm fairly certain it has a vacuum leak somewhere. The PO installed a vacuum gauge and it usually reads low. I can't hear it anywhere though.

 

[SC Rednek]

if you have one of those hand pumps for bleeding brakes they also work great for checking for vacuum leaks.

Another thought, have you ever done a compression test?

 

[Darky]

I have not done a compression test. I've been wanting to so I can check if the engine has enough compression to support the claim of a recent rebuild.

I've been thinking about just buying all new vacuum lines. I'd be guaranteed to get it then, and it could probably use them anyways. Another beautiful touch he put on: he cut the heater hoses from the heater core and just completely bypassed it.

 

[SC Rednek]

he cut the heater hoses from the heater core and just completely bypassed it.

I have that on my CJ5 and Trans Am. Perfect fix for a leaking heater core. Just put on a coat if it's too cold.

 

[Darky]

I have that on my CJ5 and Trans Am. Perfect fix for a leaking heater core. Just put on a coat if it's too cold.

Yeah, but I'd rather have heat. And he didn't even bother removing the old hoses, there's just a couple nubs left hanging there. :roflmao:

 

[Gonepostal]

I had a 55 Ford hard top that this happened on. Definitely not a fuel injected engine or a Jeep. Same scenario, loud boom and then loud exhaust. In my case it was a rich fuel to air mixture that resulted in the vehicle backfiring. Might be similar…maybe power valve on the carb or an ignition problem.

 

[91XJRubicXD]

Yeah I see the burn marks on either side, I was wrong in assuming. Didn't mean to upset you there Darky !!! I turned the signature off for tapatalk btw. Is there a speeding violation as well if you're good at typing to, lol