I think I broke it already

[mopar 3 B]

Any reason for not hooking the carb rear air door back up?

 

[moparedtn]

What else could possibly have been damaged as a result of the backfire I wonder?

 

[mopar 3 B]

What else could possibly have been damaged as a result of the backfire I wonder?

Why does the area around the accelerator pump look fuel stained?

 

[eldubb440]

could the backfire through the carb have created a vacuum leak at the intake gasket?

 

[mopar 3 B]

could the backfire through the carb have created a vacuum leak at the intake gasket?

Would have blown any pluged vacuum ports first.

 

[moparedtn]

Any reason for not hooking the carb rear air door back up?

AVS carbs have those. This one does not.

 

[moparedtn]

Why does the area around the accelerator pump look fuel stained?

This the an old reman carb that came with the engine when I bought it. It has all sorts of blemishes and such on and in it.
If it didn't come off with a good blasting of brakleen, it stayed. I ain't into polishing it; it will be replaced with a proper AVS this summer
sometime.
I even had to get a jet kit to get the jets back to "factory" when I first got it; the ones that came in it were WAY off.

 

[moparedtn]

could the backfire through the carb have created a vacuum leak at the intake gasket?

Possibly, sir. That and the carb base gasket crossed my mind also. Carb gaskets look fine; I reckon I'll hose down the intake with some Brakleen next time I have it running. Thanks!

 

[moparedtn]

Would have blown any pluged vacuum ports first.

If that's the case, this rascal only has the screwed in 1/4" plug in the back of the carb (since I don't have power brakes).
Looked ok when I had the carb off.
Come to think of it, I didn't plug off the line going to the PCV valve, but it wasn't making any racket when I was underhood.

 

[Fran Blacker]

Maybe try pulling plug wires to find out which cylinder isn't firing and change the plug? Maybe one got damaged?

 

[moparedtn]

Maybe try pulling plug wires to find out which cylinder isn't firing and change the plug? Maybe one got damaged?

Got a fresh set of eight to install sitting on my desk as we speak.
I am wondering, though:
What exactly did I prove/check by hooking up the timing light to each spark plug wire?
If a plug were damaged/fouled/not firing, would the light have lit up anyways??

 

[Fran Blacker]

Got a fresh set of eight to install sitting on my desk as we speak.
I am wondering, though:
What exactly did I prove/check by hooking up the timing light to each spark plug wire?
If a plug were damaged/fouled/not firing, would the light have lit up anyways??

Can't disagree but I'd still do pull wires one by one if you have a dead cylinder .

 

[moparedtn]

Can't disagree but I'd still do pull wires one by one if you have a dead cylinder .

I would have but I ran out of "personal gas" pretty quickly today.
Hoping some shows up tomorrow.

 

[mopar 3 B]

Got a fresh set of eight to install sitting on my desk as we speak.
I am wondering, though:
What exactly did I prove/check by hooking up the timing light to each spark plug wire?
If a plug were damaged/fouled/not firing, would the light have lit up anyways??

Light only shows the wire carried current to ground some where. If the light had not lite the plug wire would not have been any good.

 

[Cornpatch MO]

Little trick I learned, and don't know why it works---With engine running , and you have a cylinder not firing ( usually due to fouled plug) pull the spark plug cable off and hold it just a little ways from the plug so that it has to jump spark across the gap. Many times the spark plug will start firing and then you can put the wire back on the plug. ..................................MO

 

[moparedtn]

Light only shows the wire carried current to ground some where. If the light had not lite the plug wire would not have been any good.

So that at least rules out a bad wire.
Excellent, thanks!

 

[moparedtn]

Little trick I learned, and don't know why it works---With engine running , and you have a cylinder not firing ( usually due to fouled plug) pull the spark plug cable off and hold it just a little ways from the plug so that it has to jump spark across the gap. Many times the spark plug will start firing and then you can put the wire back on the plug. ..................................MO

Beats me. Amplifies the spark somehow?
Not going to happen much in this case anyways - these stinking headers won't let me do much of that.

 

[WileERobby]

Beats me. Amplifies the spark somehow?
Not going to happen much in this case anyways - these stinking headers won't let me do much of that.

The coil will only supply as much voltage as needed to cross the gap. By holding the wire from the plug, the coil will supply more voltage. Years ago, they sold these "spark amplifiers " to increase gas mileage using the same principle.

 

[moparedtn]

UPDATE 4-30-18:
I get done with work stuff and it's time to face the music awaiting me in the garage...
Plugs all gapped (all the store had were NGK V-Power. Yeesh.)
I get to where I'm feverishly working away at replacing the plugs on the worst side (passenger).
First two from back to front sure enough are gas-soaked.
Then I pull #4 and hmmm, not so bad.
I'm holding that plug up to have a closer look and then I spot it:

My immediate reaction:

Mopar 3b called it....and I'm an idiot.

Went ahead and replaced the rest of the plugs, capped off that damn port (I need to find a 3/8" plug to do the job right!) and hit the key.
Yep, she sings like she always did.

Did I mention I'm an idiot?

 

[moparedtn]

The coil will only supply as much voltage as needed to cross the gap. By holding the wire from the plug, the coil will supply more voltage. Years ago, they sold these "spark amplifiers " to increase gas mileage using the same principle.

Ah yes, I remember those!