Odd fix for backfiring through the carb

hunterhicks

Member
Dec 4, 2003
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FYI for those good kiddies that use the search feature of this site.

I had a really odd problem of backfiring through the carb when I put any load on the engine- you could drive, but you have to very slowly accelerate or POP POP goes the carb.

Edelbrock 600 1406. I totally rebuilt the carb, changed timing, changed rods and jets, you name it. nothing fixed it.

What was it?

The ignition. I had a bad plug/wire/cap/rotor- not sure which, replaced all of them at once, and it is now fixed.

Strange, eh?
 
FYI for those good kiddies that use the search feature of this site.

I had a really odd problem of backfiring through the carb when I put any load on the engine- you could drive, but you have to very slowly accelerate or POP POP goes the carb.

Edelbrock 600 1406. I totally rebuilt the carb, changed timing, changed rods and jets, you name it. nothing fixed it.

What was it?

The ignition. I had a bad plug/wire/cap/rotor- not sure which, replaced all of them at once, and it is now fixed.

Strange, eh?

It was most likely the cap...there was probably a short that was causing a cylinder to fire when an intake valve was still open.

I had similar behavior when I got some condensation under the cap...I was lucky, I simply dried it off and it worked fine.

It's always a good feeling to solve one of those pesky problems, eh? :nice:
 
Back firing through the carb often means that the timing is too far advanced. Back firing in the muffler can mean the timing is far retarded. Also, check your firing order and the condition of your wires. In the dark of the night run your car with the hood up and with a spray bottle, mist warm water over the engine and watch for sparks or arching.
 
FYI for those good kiddies that use the search feature of this site.

I had a really odd problem of backfiring through the carb when I put any load on the engine- you could drive, but you have to very slowly accelerate or POP POP goes the carb.

Edelbrock 600 1406. I totally rebuilt the carb, changed timing, changed rods and jets, you name it. nothing fixed it.

What was it?

The ignition. I had a bad plug/wire/cap/rotor- not sure which, replaced all of them at once, and it is now fixed.

Strange, eh?


Good info!
 
CARBON TRACKING

its when carbon builds up on the bottom of the cap and creates an easier electrical path to be completed by the ignition system.. then it fires on the incorrect plug... pretty simple sometimes it is very hard to see.. if you still have the old parts look under the cap for a tiny black line that looks similar to a "lightning bolt" shape thats normally the path it would take