The Stovebolt Site Forums The Shop Area Engine Shop Muffler issue

Good Afternnon all,
My name is Yori. I have a 1958 GMC series 100. It ran fine untill a massive backfire which blew out the seems on the muffler. Does anyone have an idea s to what would cause this.
Thanks.

Must have become full of fuel. Better check your carb setup. I was once riding in a F%#d pick up with a friend and his catalytic converter loaded up. The truck started snorting and running really rough until KERRRWHAM! Blew the exhaust right off and bent the drive shaft. Unbelievable. Scared the bejeepers out of both of us.


(yeah, I know....friends don't let friends drive F#rds)See what happens?

welcome to the garage yori - as Dave sez, it could only have been excess gas in the exhaust that got set off by the heat - back in the day we did that on purpose sometimes by turning off the engine at speed for a few seconds without pushing in the clutch, then turning it back on BANG

Bill

Cheers to you both. I have just finished rebuilding the carb and hope to have solved the problem. If weather permits I'll try it this weekend. Here is the truck. Thanks for the welcome. http://profile.imageshack.us/user/yorinski/

Nice truck. Hope that solved the problem.

Good looking trucks, I am jealous of your yard full of them. I also have a 1964 chevy that is my daily driver. SOmeday I'm hoping to get a 38 into the collection.

Mine was caused by a loose power connection to the coil.
pic

Could be worth a look.

regards,
Leon

Thanks for the suggestion. I will look into the coil as well. The picture you sent of yours is just about what I am looking at too. On the subject of mufflers does anyone have an opinion as to type and importance, as I will be replacing mine, I thought I might ask.
Thanks again,
-Yori

You can start a religious war by asking about muffler preferences.
I use a pair of 22" Smithys on my 235. I ran a single one after the muffler "event" until I got the dual system finished. I like the way it sounds and the low cost of the mufflers.

regards,
Leon

My muffler blow off was caused by a worn out ignition switch. It was esseintally doing the same thing as Leon's loose coil connection.

Pretty sure both my trucks have the stock style round mufflers. I like the sound alot. Jim Carter has them for like $50.

This blown-out new muffler is the result of the timing being off (we had re-installed the distributor on a GMC 270 and rotated it too much trying to set the timing "by ear").

It sounded like a cannon going off.