Need help/advice

So the cap n rotor were on the car when I got it so looks like the prev owner did a tune and got the cap half on maybe regardless I replaced it with a spare still same no idle so i did the valve adj and its a bit quieter but still no idle. Only thing left is the carb. Also this is the dirtiest engine Ive seen in a long time the oil looks like carbon on the head and inside valve cover.