85gijunk4x4

i was pulling out of my driveway heading for the farm this morning, the truck started stumbling, and then all of a sudden, the muffler exploded...(it was loud, almost like a sonic boom!!...well not really, but it was loud as heck)...

after that it ran like normal, just alot more exhaust noise. is this normal at all? ive never seen or heard of it happening at all before. what would cause this, a plugged muffler?

i was in second gear, about 20 mph, wasnt over revving it, or bogging it, just driving like a grandpa as usual.

pulled over to take some pics....

peow130

plugged up exhaust tip causing extreme pressure?

fishtruck28

your not going to like this, but, the same excact thing happend to my 4runer a few miles later it developed a noticeable tick in the motor sounded like valve seat(s) flopping. pulled the head, great shape, then i looked in the cylender wall scored up and down,.
rings must have froze then broke
im currently looking for a short block 3.0
ill take pics of muffler tmrw

85gijunk4x4

cant say that was the cause...the exhaust broke off about 4" past the muffler, and a few days ago, i could practicly see into the muffler....i dont see what could have plugged up the tip of the exhaust pipe in a matter of 2 or 3 days...

85gijunk4x4

well that doesnt sound too good....im guessing if my rings froze up and broke, i would be able to hear the tick now correct?

so bassicly theres a chance that one of my rings broke, and if i keep driving it, it will score the cylinder wall?

fishtruck28

do a compression check i had #2 wouldnt get over 120 psi
also the tick is hard to hear becouse your muffler exploded
probally from blowby accumilation in your muffler + spark

KFP

Do you still have a catalatic convertor? if so you could have blown something from it to the mufflerand plugged it off.

85gijunk4x4

ahh compression check, good idea!!
and yeah, i cant hear anything besides exhaust noise...

im about to post a video i took from about an hour ago when i got home....

god, the only truck i had that was quiet blew up the muffler...i have no luck...and the sad part was that i was actually going to keep the truck quiet too. i kinda miss having a quiet truck already

85gijunk4x4

yup, ive got a cat. i was thinking the same thing. tomorrow im going to check the spot i was at when it blew, and see if i cant find peices of the muffler baffle, or peices of the cat that couldve plugged it up.

would a plugged exhaust cause the truck to "stumble"? once it blew the idle went back up to normal (it was idleing roughly at about 300 rpm, i had the clutch in so bassicly it was in neutral)

85gijunk4x4

85gijunk4x4

(^^^^click for video^^^)

offset442

I doubt anything could have clogged the exit pipe and have caused such a complete fragmentation of the muffler housing, What you have there is extra fuel and a lot of it almost stoichiometric to have cause that much expansion velocity accompanied by an ignition source such as a leaking ex valve, or a chunk of burning carbon, I would also hazard a guess that the cat is for the most part an empty cheater chamber..........

.......Which leads to the opposite problem........ an Oxygen source: Such as a existing hole in the muffler or an exit pipe that is too short, in your case about 4 inches. If the engine is producing lots of extra carbon monoxide also known as "producer gas" that counts as a fuel source as well an can ignite and blow up the muffler with considerable force.

Ocean

MaK92-4RnR

This was caused from the pipes being clogged. The stock muffler has a seam in it, pressure built up, and blew out the seam. you're lucky it didn't cause any further damage.

The source of the clog is definitely a mystery though. carbon build up could be one, or maybe rust. who knows.

James Woods

iTrader: (1)

http://youtu.be/HktV2yGtLv8

MaK92-4RnR

^^^ thats the conclusion... yep. definitely it. haha <3 Beverly hills cop.

peow130

Varmint in the exhaust is my guess. Cant find him cuz he scurried away

xxxtreme22r

I had something similar happen on an old 2.2L cavalier. Not that bad but enough to puff the muffler out. My dumb arse had a plug wire or something backwards added to some residual carb cleaner in the cyls after doing a head gasket on it and it backfired and blew it out.

85gijunk4x4

so i think i might have figured this out, thanks to yotatech adding dates to their threads!!

here is my thread from the click but no start problem i was having on 3-26-2011

https://www.yotatech.com/forums/f120...-start-232300/

this was solved on 3-29-2011, just 4 days before my muffler exploded...

now when i had the click but no start, the fuel pump was running when the key was in the start position, but the engine wasnt turning over, so i had probably dumped alot of raw fuel into the engine, but since it wasnt running it never got burned off.

somehow or somehwere along the line i guess the fuel made its way into the exhaust system and then detonated.

i thought of this out of the blue a few days ago, and i give a big thumbs up to YOTATECH for adding dates to their threads!!

cody o

Had this happen to my 91 4runner 3vze. After working on the heads, I installed the distributor 180 degrees off and proceeded to crank it for about 45 seconds.

greaseball

i had this happen to an ex-girlfriend. i did a tune up on her 72 dodge with a 318 and it was late and i put the dist in 180 out and cranked it it would not start so not thinking i pumped the gas a few times and cranked it some more when the muffler expolded at 2am it sounded like a cannon going off. it woke me up i moved the dist 180 and it fired right up and ran smooth so i shut it down and went inside to bed before the popo showed.