It doesn't take much to foul plugs. Just running at idle with too rich a mixture, blown power valve, floats not set right or a piece of snot stuck between the needle valve and seat (on the floats) would do it.

Does she run rich at idle before she croaks..such that yer eyes water and smells bad?

Pull a plug or two and check.

 

It didn't. It ran perfect that I could tell. No smoke smooth idle. I press accelerator and it boggs down, backfires. It smokes when pedal is pressed. Black smoke.

 

Ok...pedal depressed, bogs down, backfire (through the carb or exhaust?) burns black smoke. Sounds like yer getting enough gas but the engine firing (timing) isn't advancing to compensate for the extra fuel.

Have you reset the timing?

Time to pull the distributor cap and check a few things. The breaker plate has no slop in it - up & down, but easily moved by suction at the vac advance can? Is the rotor free to move - only a little - by turning it a bit?

 

This is the number 1 plug number 2 looks the same.

 

Yes,new plugs can foul. Pull the plugs. If they are all black with soot ,you are getting WAY too much fuel. Check the float levels.

 

It's a brand new carburetor. Where does the cycle end? New plugs, new oil and filter. Keep repeating the process until it gets right. I bought all new to get it right. My oil that I changed yesterday is starting to turn black. I'm getting frustrated.

 

Holy Carbon Fouled to the max!!! Is that crud I see between the electrode and ground? Or is the gap that small? Gap = ~ 0.044"

I know we all threw you a bunch of tests to do... have you done some - such as timing, ported vacuum, mixture settings, float setting, distributor checks, etc.

Was the carb new from the box or new to you from a friend? If it was from a friend, maybe the jetting is too high.

Do the other checks, and let us know what you find.

I can feel your frustration....

Does yer oil smell like fuel? Take a whiff and let us know - could be yer floats.

 

I have had several new Holley carbs have a bad float right out of the box, would do fine then overflow the bowl and flood engine. Check float levels, as DB249SCJ said.

 

I've not done toon much today. I'm so pissed right now. The carb is brand new. The gap is set at .044. When I bought the truck 4 months ago none of the plugs were gapped the same and none were gapped a .044. Will do. Right now I have a valve cover leak. 😠 new gaskets, just my luck. I've got to get that fixed first. It's pouring on the headers smoking bad.

 

Will do thanks. I bought new to avoid problems.

 

New carburetor is NOT "plug and play"! They need to be adjusted from scratch.

They will run out of the box, but the float level or, actually fuel level, needs to be checked and adjusted. Did you check that power valve is tight?

The basic fuel height is affected by the volume and pressure of the fuel pump. We can make ballpark or "bench settings" ("dry" float height) but that's just to get close. FWIW, any time a new fuel pump is installed, the fuel level in the bowl should at least be checked.

Think of a bucket full of water. A series of holes in the side of the bucket. The lowermost opening will project a stream of water to flow farther than higher openings, because of the increased pressure in a taller column of water, as every schoolboy knows.

Same principle applies, same thing in a carburetor fuel bowl. So the manufacturer has an acceptable range of fuel level low/high that must be maintained at all times, under all conditions, from idle to WOT. Otherwise it will choke and spit under full throttle or flood out, start a fire, etc. The fuel level also will affect jetting requirements to some degree, and the idle mixture screws best "lean drop" setting.

The ignition timing will affect engine vacuum, and this changes the ideal mixture setting a little bit too.

That's why ya gotta start from the beginning and the stock OEM base settings, and build from there, step by step, brick by brick. If a certain initial adjustment is off, other settings farther down the line are often compensated to try and make it work, but it will never run right, or will have serious issues in cold weather, or hot weather etc. Not trying to beat up on you here, but explain what happens. I did the same thing when I bought a Holley 500 CFM 2 bbl on the advice of a clerk somewhere. I bolted it on and it seemed to run better. The plugs were constantly fouled.

That's some serious fouling! It's not as bad as running too lean, but excessive fuel will wash out rings and dilute crankcase oil.

 

Extreme amounts of truth here. I just went through this, and am just now seeing the light. Can't go wrong with OEM settings to start out.

 

Now I don't take it the wrong way. I need to hear this. I thought it was as you say, plug play. I will make adjustments.

 

Okay. I check timing. Number 1 plug is top dead center, the rotor button is turned toward number one plug wire. But the timing mark is not on the arrow. I do not understand anything I'm telling you. The timing indicator is lined up with Harmonic balancer number 10. Moving up the Harmonic balancer there's a number 0, moving on up there is a number 10. That is where a white Mark is on Harmonic balancer. It's a chalk Mark. Directly on the opposite side of Harmonic balancer there is a groove that is painted white. There are no numbers printed around this painted mark. The frustration continues.

 

The first number (10) is After Top (dead) Center....ATC on the balancer. You don't want this number.

Then there's a "0"...."10"....."20"...etc. The "0" is zero degrees BTDC, BTD on the balancer, the "10" is ten degrees BTDC, and so on.

Line the pointer on the block to just before the 10 on the balancer - the second "ten." That'll give you about 8* BTDC.

I try to make sure #1 piston is on the compression stroke, just about at the top of its travel and the rotor is pointing at or just after #1 plug wire.

Start 'er up and fiddle with the timing after she's started - with a timing light of course.