There are big differences between the 24T and the 224T. The T simply means it is a twine baler instead of wire tie. The 24 was the light duty and the 224 was the heavy duty. Pick ups were the same size, but the plungers and chutes were completely different. Knotter are identical from the 14T through the early 337 and 347. At some time in the **7 series JD went to split knotters. The light duty 24T has the plunger on skid blocks on steel rails, and the 224 has bearings holding most of the weight of the plunger other then the far front right corner. The 224 plunger design is still the same basic design that JD still uses today. 24 usually had a mechanical thrower if it had one, and the 224 had the hyrdaulic 30 that was used on the 336 and 346 and some in the 337 and 347. 224 has a few more strokes per minute also.
The gentle men having trouble with his 336 and consistency, that is usually caused by the operator. All balers have the same situation with knotter trips. Once the guage wheel trips the knotter, the baler puts one more flake on before it ties. This is just the way they all are. If you are make small flakes say the normal 2-3 inches thick, no big deal, but if you are really jambing it down the baler, you can add even as much as 6-8 inches in a single flake. It is up to the operator to be evenly feeding hay into the baler. If the operator is in a hurry, bales will become irregular. Windrow size and how fast it is being feed has lots to do with it also.
In a JD baler with the auger feeding into the feeder finger, there are a few tricks. First try to pick up the hay on the right side of the pick up as much as possible. Second the hay should be standing up behind the auger just infront of the feeder fingers. If it is not you are not putting enough hay in, either pick up your ground speed or make bigger windrows. If the hay starts coming over the front of the auger, the opposite is true, slow down.
Any other questions, just ask away.