Whats Wrong When Gas And Flames Shoot Out Of The Carburetor Of A 350 Chevy

Posted in Fuel Systems & Components | Asked on Feb 15, 2011

The truck had been sitting for a year, so i siphoned the gas out of the tank and refilled it, and it started just fine. Drove it down the road for a sec came back, parked, and engine was idling just fine. Shut it off and 2hrs later tried to start it and it wont. Has a all msd distributor, electronic ignition, coil, and Edelbrock carb and intake. While cranking it backfires through the carb, shoots gas out of the jets on top of the carb at regular intervals, and has also caught fire. It tries to turn over while cranking, but just wont quite do it. Has a hard spot in the cranking process that about brings the starter to a stop sometimes. Sounds like timing, cause i know its getting fuel. Just dont know where to start. Could it have jumped timing??? Just weird that the truck was just running fine.
I have taken the top off the carb and the floats seem to be fine. The distributor will not move if i try to turn it.

There are 7 Answers for "Whats Wrong When Gas And Flames Shoot Out Of The Carburetor Of A 350 Chevy"

  1. Kelly_f_1999 says:

    Timing yes that or too much fuel

  2. Chevyss396427 says:

    Take off the carb and clean it. after sitting for a long time the jets can get all gunked up as well as the bowls and floats, make sure the fuel system is totally clean as well, put the carb back on and set to timing to straight up then give her hell.

  3. Dan W says:

    I think you have a sticking Intake valve. It stays open while under compression and pushes air/fuel back into the carb then ignites it. The clue is the ” regular intervals”. INSTANT FLAME THROWER1

  4. Adam H says:

    Check your float inside the carb it could be sticking

  5. Hummertech H3 says:

    Sounds to me like timing too, could have had a loose distributor hold down bolt, that’s the most likely, also could be a stuck or burnt intake valve causing it to spit compression up through the manifold, i’d doubt the timing chain jumped if it was running fine before you parked it, also could be the flyweights on top of the distributor stuck and has the timing over advanced. i’d double check your timing and then pull the cap and rotor and make sure the weights are working right and the springs aren’t broken, then check the timing again with a timing light.

  6. Baldie says:

    It sounds like it jumped time or too much gas coming into the carb.

  7. Mdk68gto says:

    The fuel is pumping out the vents because the needle and seat have failed. appearance means nothing, the flat could have a hole in it and sink to the bottom. as for the backfire that sounds like timing is off. check timing to confirm that it is correct. it could jump timing in some situations but you can test for that.