Before you remove the carb, check to see if you have "nozzle drip" and/or signs of obvious flooding (fuel covering the air horn, pouring into the engine). Needle and seats can fail out of the blue no matter where it was sourced from, even w/o debris. Did you call the gas station? We had one here not too long ago that had water in the diesel fuel. I called the station on behalf of my customer, and they actually admitted it. The station's insurance co had to reimburse my customer the over 10k bill that it took to install the "decontamination kit" in his LML.
It seems like everyone is on the Fuel/carb being the problem, my money is still on the coil or ignition, spark, 8 V. Will cause these symptoms 99%.
I removed the carb yesterday and did the "blow test". It passed. Today, after installing the new plugs I'll do the second test and crank it up to see how it runs. By the way, can I tell with the carb off if the well plugs are leaking? That's another possible problem area.
if your into removing the jets, you can coat the well plugs with dishwashing soap, direct compressed air at the main, secondary wells while holding the carb body upside down. If you see bubbles form, they leak. Its in Cliff Ruggles qjet book.
9.6 volts with a points ignition is sufficient. The Lectric Limited Breakerless is similar to points, so am I wrong for thinking you might need to swap coils and see if the voltage jumps up a bit? I had a similar issue a couple years ago and ended up going back to the Delco 247 coil I had in stock and the problem was resolved. Just a thought....
A weak spark generated by a faulty coil will leave lots of unburned fuel resulting in a overly rich, black-oily spark plug appearance. When all of your fuel/ carb problems don’t Pan out, maybe look in this direction?
I myself have only had one coil cause a running issue,..had plenty just take a **** ,...and do nothing...it was an accell coil that was weak,..would idle ok but any load and it ran like goat **** As Bob said needle and seats can drive you crazy,....run fine one min,..run great for two days then go to **** again,....if it's running and not popping and such under load especially,....it's fuel issues most likely Look at the cone of the needle if there's ANY sign of a groove it's garbage,..and to be honest if I've removed the air horn ,..I'm replacing it anyway and cleaning the bowl out,..you would be surprised what can make it past the filter somehow,..and or down the vent tube,.. remember it's not filtered and we all have seen debris get in the breather
Float that is too high flooded engine after going around corner and is just high enough to flood but not see it. Coil only went out 1 time and car would run, if you got it started, it was rough under power. Diesel fuel got dumped into wrong tank at gas station from supplier
Here's the latest update... I installed new plugs and re-installed the carb and filled the float bowl from the vent tube and the car started and ran fine for about 20 seconds. I then re-connected the fuel line and it still ran fine. I then pulled #1 new spark plug after idling in the garage at about 1000 RPM for about 10 minutes and this is what it looks like! I can’t see the carb being that rich at idle so, it almost has to be bad spark? I did turn the carb upside down while it was off and seems the needle/seat is working to block air blown into the fuel inlet. I’m ‘gonna replace the coil with another Delco stock coil to see if maybe that’s it. Both the coil and Lectric limited module are the same units the motor was dyno'd with two years ago. )(I have a sneaking feeling the problem is with the Lectric Limited module) Here’s a link to the spark test on the #1 wire removed from the plug while idling at about 800. Looks weak to me but, I have no frame of reference to compare it to. The spark wouldn’t jump a much larger gap than this at all. https://youtube.com/shorts/0JscCHupZvU?feature=share
Does you car have a choke? If so you need to let it warm up to normal temp. The plug definitely looks way over rich, but if the choke is on (pull off functioning?) that might be causing it. You said the car ran ok, so unlikely to be spark.
Yes, I have the factory choke on the QJ set to just barely engage on a cold motor because the aluminum heads don't have a heat crossover. But the choke does release fairly quickly and I did run it in the garage for about 10 minutes at about 1200 RPM until the choke released and the motor was up to operating temp. Is it normal to coat the plugs with the choke on and will they burn off when the car is driven normally? I didn't think to check the plugs during the first 3 or 4,000 miles since it was new as I didn't have this problem until it started to run really ruff last week.
Hmmmmm, maybe the old guy from Missouri knows a thing or two………….it’s the spark Ray, not the gas. Just Bustin’ balls alittle. I experience these gremlins myself all the time with my classics in the garage, always chasing something, but it sure great having the V8 board to get various opinions for sure, none of us know anywhere Near enough!
If the car seemed to be running ok, I would take it out and rally around abit, then go home and pull the plug.
garage idling is not a test..... That soot is literally common with todays garbage lead less gas.... Get that thing on a open hi way ,,,,, Run it hard,,,,, pull over in a safe place. kill motor .... pull plug on the side of the road.... NOT in your garage.
This. You want to "read plugs", you have to put in new/clean plugs, make full WOT pull, and shut down and read the plugs. If you idle, run at WOT, then idle, low idle cruise to more than a minute or so, you will be looking at a plug with the "idle and likely rich" realm of operation. "Plug reading" is a bit more difficult today than what we did 50+ years ago, with higher octane and leaded fuels. It does not mean you cannot read plugs, the timing (ground strap line) or insulator, as well as the first "ring" of the plug thread(s) into the chamber, but it is not exactly the same as the way we saw plugs back in the old days. Find folks that actually understand this "voodoo" and let them guide you. Or else you will be chasing your tail and the old wives' tails. (Not the tail you wanna be chasing...)
I live in Washington we have the worst gas in the nation.. So that is how we do testing here.......... Apparently you have better gas....
In the "old days" plugs would show "tan" when things were good, even after driving for hundreds of miles under varied conditions. Now, if you drive for days/miles your plugs will often show almost nothing (lily white) or blacker than a coal miner's ass in the back hills of Kentucky. Just no consistency over time. Hence the need to do a "new plug, hard run WOT, shut it down, pull and read the plugs". No doubt there will be a bunch that will argue against this, but with the gasoline being all over the place today, compared to the "more consistent" gasoline that each person was familiar with, the proof is in the testing/science and making notes of all parameters in the observation. Otherwise, call it "guessing".
