I bought 2 government surplus hydraulic power units that had 16 hp 341 engines. The engines believe it or not were pull start. I installed then in 2 different Case 224. I used the 14hp flywheel, starter and other parts to convert them to electric start and battery ignition. The Case pump adapter bolted right up, but required shorting the crank. I had to use the 14 hp pan. To use it I had to make a metal plate that went between the pan and the engine to cover the openings on each side of the block. I also used the 14 hp carbs because the throttle and choke connections were different. I also had to get a new coupler half for the lovejoy. They were nice running engines and the price was right.
I installed a K-341 AQS IN my Case 444. I used a combination of the sheet metal parts from the K-321 and 341, and the oil pan from the K321. The biggest challenge was the exhaust, which is 1.25" on the 341. I used a 1 1/4" street ell 45 to get the exhaust turned to the outside of the engine, and a Jacks small engines quiet muffler. The bottom end of the quiet muffler is braced to the engine mounting plate. I had to cut down the K-341 air cleaner which was off a Cub Cadet 1650. There was still room for the stock filter element. The K-341 AQS is a quiet series engine which is more quiet than the K-321 and seems to have more torque. Nothing on the tractor itself had to be modified. Been running this engine for about 6 years now, a nice upgrade.