I've got a 56 Chevy 210 with a 235 and a 'glide. It has 60,000 original miles and has been in my family since brand new.
I don't drive it more that once a month and then not over great distances, just around town.
Recently, it started to idle in nuetral or park like it had a long duration cam. Actually sounded kind of cool. Once you started accelerating, it smoothed out and when fully warmed up the idle evened out to a degree but still kind of loped. Lots of black smoke from the tail pipe.
Then it got worse. Under power is started to miss even when fully warmed. Not badly but just noticeable. If you'd stick you foot in it, it was fine.
I figured that I'd just pull a plug and see how it looked since I've never changed one in the ten years I've had the car. It always ran smooth as silk so I never bothered to tune it.
Before pulling a plug, I got my wife in the car and had her keep the motor running while I sprayed carb cleaner in and on the carb. Still idled like crap spewing black smoke out of the tail pipe.
Then I pulled a plug. Dry but black soot covered it. All of them looked the same. I put fresh plugs in and fired her up. Still loped at idle, but not as much. Ran it down the street with the air cleaner off so I could pull over and make sure the choke was opening as it warmed.
Within a mile and half it was running smooth under power and the idle was not as choppy. I pulled over and the choke was about half way open. If I opened the choke all the way, the ilde would drop in RPM and smooth right out. Blip the throttle, choke partially closed and idle got a little choppy.
Drove a mile and half home and by the time I got back the idle was glassy in gear and out of gear.
What does anyone have as a remark or advice to this scenario, please?