Why is my Carb on fire?

[4drplymouth]

Just upgraded my 67 273 commando 2bbl to a 4bbl. Was lucky to have found a 67 273 4bbl intake and I went with a Holley 4160 w/ electric choke. Easy swap. First attempt to start it yesterday and the carb caught on fire? The car ran smooth with the 2bbl. With the 4bbl - fire.
Any ideas whats going on?

 

[dave5237]

Check the timing. Could be a backfire issue.

 

[4drplymouth]

Will do - Thanks

 

[daredevil]

did you by chance flood it?

 

[RustyRatRod]

Your carb is on fire because gas found a spark.

 

[tpodwdog]

how do you have that electric choke wired?

 

[sublimegtx]

Your carb is on fire because gas found a spark.

LOL... again Rusty

 

[dave5237]

how do you have that electric choke wired?

I know where your going. I had mine hooked temporary to constant 12v and man did it get hot.

 

[4drplymouth]

Guess I have to go back and check the positive connection of the elec. choke. Didn't really have a chance to flood it. By the third crank the motor wanted to turnover but thats when I saw the flames. Then I tried it one more time all flames without even fully turning over.

 

[WP29440SE]

whatever you do , dont use windshield washer fluid to put it out

 

[Photon440]

Your carb is on fire because gas found a spark.

That's the trouble with spark plugs. Using these, problem solved:
http://kalecoauto.com/index.php?main_page=product_info&cPath=9&products_id=30

They also have such useful items as cross-drilled brake lines, blinker fluid, Elbow Grease, Radiator insulators, muffler bearings...

Back to the OP. Did the engine catch and run at all? Is the distributor correct? Any fuel dribbling out that might indicate a high float level or gasket leak?

-=Photon440=-

 

[RustyRatRod]

Hard to believe someone would dedicate an entire web site for a joke. That's hilarious.

 

[Dako]

I agree with Dave (timing).

Did you change the manifold with, or without, removing the distributor? If you removed the distributor, you may have the timing off. Even a slight (quiet) backfire through the carb can get things going.

 

[4drplymouth]

I kept the distributor in place. No change there. Thats why I'm a little confused. Could changing a manifold and carb effect the timing?
I'm getting flames with each crank. I cant even get it to run a few seconds with out the flames coming up? Going to go down the list tonight starting with the choke wiring.

 

[Photon440]

I'm not really familiar with small block intakes. Is it possible that there's a crack in the exhaust crossover that's allowing intake fuel to mix with burning exhaust gasses? Just reaching for ideas here....

-=Photon440=-

 

[PurpleBeeper]

I kept the distributor in place. No change there. Thats why I'm a little confused. Could changing a manifold and carb effect the timing?
I'm getting flames with each crank. I cant even get it to run a few seconds with out the flames coming up? Going to go down the list tonight starting with the choke wiring.

No offense, but I think you missed something.....maybe the distributor did move somewhow?....maybe a couple plug wires got mixed up? I'm guessing you didn't touch the cam/timing chain, right?

Carb fire is a symptom of an open intake valve + spark when you don't want it. I suggest you double check TDC vs. #1 cylinder, firing order vs. wires, distributor rotation direction, etc.

Good Luck.... you'll get there!