29 minutes ago, Dave WM said:

the black is a result of trying to compensate for 4 others that are not working at all.

He has carbs though.  What would the "compensation" be?  The air-fuel mix happens at the carb and should be essentially the same for each of the three runners being supplied. 

The other side of the view would be "how can an engine run on two (or three) cylinders.  Assuming the clean ones are "dead" and the dirty ones live.  He said that those plugs were actually in the engine but there's no way to confirm.  Hopefully he wasn't just putting new plugs in the picture for comparison.

One reason we've focused on ignition is, like you said, internet diagnosis is difficult.  If we could confirm that spark is good for all six then we could ignore spark and focus on fuel-air, or oil, or compression, or valve timing, etc.

The power balance check is a good idea except for the fact that he has electronic ignition.  And ignition modules tend to be sensitive to having nowhere for their spark to go.  He might fry his Pertronix module, as CO implied in his comment.

 

1 hour ago, madkaw said:

Blown head gasket? 

I thought it might be bad valve seals myself.  But folks are fairly convinced that the fouling is fuel fouling.  My old 76 engines with worn valve seals had all six plugs pretty dirty, but not wet though.

He says that all six cylinders give a solid 180 psi pressure reading.

Someone got, the firing order off the top of your head?

I'm not trying to crush ideas, just reviewing past discussions with Jalex and others.  The simplest solution would be to find a mechanic who knows engine basics but they seem hard to find down there.  Any good mechanic would look at those six plugs, if they are actually new and came out like that, and have some ideas. 

The picture of all six plugs fresh from the engine is new info.  Seems much clearer than any of the past discussions about Far311 cams, and percolation, and poor idle.

2 minutes ago, Patcon said:

Someone got, the firing order off the top of your head?

That's a good one.  1-5-3-6-2-4 is correct.  Maybe he some wires switched.  That fits bad spark.

3 minutes ago, Zed Head said:

That's a good one.  1-5-3-6-2-4 is correct.  Maybe he some wires switched.  That fits bad spark.

I was mainly working off your theory on bad pickups. I was hoping 3 and 4 were adjacent, suggesting a damaged section. However they are exactly opposed...

21 minutes ago, Zed Head said:

I thought it might be bad valve seals myself.  But folks are fairly convinced that the fouling is fuel fouling.  My old 76 engines with worn valve seals had all six plugs pretty dirty, but not wet though.

He says that all six cylinders give a solid 180 psi pressure reading.

You can still have good compression with a blown HG. Might be enough coolant to foul plugs but not to cause a smoke. Need a pressure checker to find it 

could feed up some solid copper up the boot, exposed wire could then be grounded to kill the spark. I can't imagine it NOT having a power balance problem though. from the look of those plugs I would think it would idle terribly.

Are those NGK's? Doubt if it's the problem but they have a tip that screws on where the plug wire connects. They can get loose. I remember someone said they can misfire if they get loose. I always tighten mine up a bit (using finger-muscle not pliers) when installing plugs.

My vote goes with incorrect firing order if wires were recently removed.

I think if he had a wire swapped it would run more poorly than it does

What he really needs is a substitute dizzy. That would eliminate the pertronix as an issue

What he really needs is a competent mechanic, as he does not posses and has not learned  the skills himself!

There have been so many issues with this car the owner could , by now, have paid a Z specialist an all expenses paid vacation to Panama for a month to work on the car and he would  come out $$$$$ ahead.

Especially if you make any accounting at all for aggravation.

My trusted mechanic, Jose, is from Honduras and cut his automotive teeth as a child learning firsthand from his grandfather and dad what it took to keep cars and tractors running dependably and indefinitely. They were extremely poor by U.S. standards and there was no running off to the dealer or parts shop for anything but the most vital of components. They ingeniously made do with what was on hand. I am constantly amazed at Jose's ability to read complex technical information in ENGLISH and comprehend what needs to be done, step by step, to effect a proper repair. He does not assume, jump to conclusions, or deviate from his methodical approach. Mechanical devices don't run on  "maybe", hope,  and wishful thinking.

The Moderators have my permission to flag this rant as "Not Constructive".