your exhaust must have been full of fuel
What could cause this???
Thread Starter
Racer
Joined: Dec 2007
Posts: 445
Likes: 2
From: Thomastown Mississippi
What could cause this???
1977 Vette, stock 350 L48, I just finished installing my new fuel pump, pumped the accelerator a few times, then tried to start it and Boom-it backfired so hard it actually expoded the right muffler and blew it off the car. I marked the three lines going to the fuel pump before I removed the old ones, so I'm sure they're on correct. I removed the push rod and applied grease to it to hold it up while I installed the pump, so I think that part is right also. What could have caused this strong of a backfire that would explode the muffler?? I'm scared to try and crank again until I know what went wrong.
Kenny
Kenny
Thread Starter
Racer
Joined: Dec 2007
Posts: 445
Likes: 2
From: Thomastown Mississippi
It must be OK. I let it sit a few minutes, bumped the starter, and it fired right up. Running really smooth, except it's really loud. I think the problem was that I forgot I had unhooked the hot wire to the distributor earlier. When I first tried to start it with the new fuel pump installed, I kept pumping the accelerator, forgetting the hot wire was unplugged. When I plugged it back in, that's when it backfired. Scared the shi$$ out of me. Couldn't believe it blew the muffler apart.
Starts right up now though, nice smooth idle. With the old fuel pump it was getting hard to start.
KC
Starts right up now though, nice smooth idle. With the old fuel pump it was getting hard to start.
KC
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
It must be OK. I let it sit a few minutes, bumped the starter, and it fired right up. Running really smooth, except it's really loud. I think the problem was that I forgot I had unhooked the hot wire to the distributor earlier. When I first tried to start it with the new fuel pump installed, I kept pumping the accelerator, forgetting the hot wire was unplugged. When I plugged it back in, that's when it backfired. Scared the shi$$ out of me. Couldn't believe it blew the muffler apart.
Starts right up now though, nice smooth idle. With the old fuel pump it was getting hard to start.
KC
Starts right up now though, nice smooth idle. With the old fuel pump it was getting hard to start.
KC
Sounds reasonable to me, 
or maybe a little louder.
Safety Car
Joined: Sep 2005
Posts: 4,213
Likes: 643
From: Orange County Ca
I'm a little older than you, and this was normal procedure for us when screwing around when we were 16 yrs old. Get the rev's up, turn off the ignition and keep the peddle to the floor so that the exhaust would fill with gas, then switch on. More than 1 muffler went south doing this. Didn't appear to damage the engine. I don't think you can do this with FI.
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
I'm a little older than you, and this was normal procedure for us when screwing around when we were 16 yrs old. Get the rev's up, turn off the ignition and keep the peddle to the floor so that the exhaust would fill with gas, then switch on. More than 1 muffler went south doing this. Didn't appear to damage the engine. I don't think you can do this with FI.
That sounds like a blast!!!Sorry, couldn't resist.
It does sound fun though.
Thread Starter
Racer
Joined: Dec 2007
Posts: 445
Likes: 2
From: Thomastown Mississippi
My wife and I got a good laugh out of it too, once we realized the car was still in one piece, minus a muffler. The muffler looks like someone stuffed 4 or 5 m-80's in it and lit them all at one time. When it blew we were inside my enclosed shop, and it rattled the walls. My wife was actually looking under the front of the car, around the fuel pump, checking for leaks when it exploded. Didn't know the old gal could move so fast. lol. Well it's off to the muffler shop Monday. After looking at the muffler again, I'm really surprised it didn't damage the fiberglass around the rear wheel. Anyone out there planning on installing a new fuel pump on their C3, check with me first. I can tell you what not to do. lol.
KC
KC
Racer
Joined: Jan 2008
Posts: 386
Likes: 0
From: macks creek mo
I'm a little older than you, and this was normal procedure for us when screwing around when we were 16 yrs old. Get the rev's up, turn off the ignition and keep the peddle to the floor so that the exhaust would fill with gas, then switch on. More than 1 muffler went south doing this. Didn't appear to damage the engine. I don't think you can do this with FI.
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Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
I'm a little older than you, and this was normal procedure for us when screwing around when we were 16 yrs old. Get the rev's up, turn off the ignition and keep the peddle to the floor so that the exhaust would fill with gas, then switch on. More than 1 muffler went south doing this. Didn't appear to damage the engine. I don't think you can do this with FI.
