Carbs - popping sound

[leedurrant73]

Hello,

Recently had my carbs rebuilt and installed, car seemed to be running fine but the popping noises seems to be getting more frequent. Seems to happen when I take the power off. Is the curable ?

One other question I have is. How do you know if you car is not running on all 6 cylinders. Thought I would ask.

Thanks Lee

[gsjohnson]

Any exhaust leaks?

[edmayo]

Did it do this before the rebuild? Any exhaust system work done at the same time? Did it do this right away as you drove away, or did the noise start sometime later? What kind of car? what kind of carbs? original install or later addition? Does it pop out the intake or exhaust? Were any jet sizes changed? Any ignition work done? You can use an infra red heat gun aimed right at the exhaust pipe exiting the head and see what the temps are. one cylinder colder than the rest is your culprit.

[gsjohnson]

What he said...

[leedurrant73]

Hello,

Carbs were taken of cleaned and rebuilt, they are 40 IDTs. New SSIs and new twin stainless outlet installed.
The noise has recently got a little worse but not sure if its coming from the intake or exhaust. It only
Does it while de accelerating. Not while going up through the gears. Nor when just idling in the garage.

It's a 69t but with 2.2t engine fitted with S pistons and barrels, solex cams and E dizzy.

Can this do any damage?

Thanks Lee

[edmayo]

It could be simply a piece of dirt finding its way into an idle jet, that's why I asked if this started immediately after the carb work or some time after. It is also useful to know if this problem existed BEFORE all this work was done. IF it were dirt in a idle jet I would expect it to show at idle also, but that may depend on how sensitive your ears are. In less time than it takes to type this you can pull all the idle jets and be sure they are clean. I don't know what muffler you have, but if the noise DIDN'T exist before putting this muffler on, then put the old one back on and see if the popping quits.

[leedurrant73]

Hello Ed,

I was told to give the car a good blast because it's only done 70 street miles since an engine and carb rebuild.
So I drove it for about an hour to burn any unburnt fuel sitting around.

Believe it or not the car is not making much noise now, I guess it just needed a good blast on the motor way.
I'm hooked, the car sounds great and performance is just what the Dr ordered. Having the S p&c's and the Solex
Cams with E dizzy really made to difference..

Appreciate your support - thanks Lee

[edmayo]

From that description it might have just been spark plugs that needed to be blasted clean. That shouldn't really happen though with the right heat range spark plugs and a strong ignition system.