Diagnosis help - cylinder not firing

[toddu]

At least I think it's not. I can pull the idle jet out of the carb and nothing happens. Exhaust note is off as well. Cleaned carbs (while still on the car). Bowls were dirty. Thought that would help, but didn't. Plug on cylinder is sooty black. Jets are fine. Plugs aren't wet at all.

Going to swap plug and hope that fixes it. If not I'll remove that carb and clean it better. Air filter housings aren't sealing, so need to fix that.

Todd

[Joe Bob]

Check for spark, could be a bad wire or cap.

[strictly]

as above, check for spark, just pull the spark plug out and plug the lead in, and make sure the spark plug is laying on some bare metal (so it earths). Obviusly don't set anything on fire. The start err up, and look to see if it has spark on that lead. You could do all of them and have someone crank it over for you. Thats much safer than trying to hold a spark plug to check! Also just to be sure, do a compression test on the cylinder you are having a problem with just to rule it out.

If it has good compression on that cylinder, and spark looks the same as other cylinders, then 110% focus on the fuel/carbs.

Blockage in idle circuit? Have you checked your float levels with the tool? Although this would be noticiable right through the rev range

[toddu]

Unfortunately it's just me, so some diagnosis is tough. I cleaned the plug up and put it back in. Started it up and it smoked (grey\white) pretty good for about a minute. Cracking idle jet caused a stumble, so it was firing that cylinder.

So, carbs are off now. Going to clean them good. Ordered some new plugs, so we'll see next week how it goes.

The standoffs for the rain hats are just too tall for the filters. Had no idea. I'm going to add some foam weather strip to fill in the gaps.

Todd