Don do the Aps caps fit on the Claas Aps Drum or do you need a sunnybrook Aps Drum? Been following your zero degree Aps threads and it sounds impressive. The anti plug turns the feederhouse off way too often in peas and canola.
Claas answer is to speed up the cylinder, which does feed way better, but it Cracks peas and canola too much.
I only mention the combine trading often because you would not really experience the long term wear, durability or maintenance.
The complete drum idea got axed. Version 1.0.
Simply unbolt stock cap, discard cap, bolt, washer and nut. 4 parts.
Bolt on ZAPS with serrated flange lock bolt. 2 parts.
If done without doing anything else lower headerless feeder all the way down to do through top feeder door. Remove the two cylinder bolts for speed range changing, leave them out, allows easy turning of just APS and cylinder.
The lastest ZAPS versions (about 2.3 and 2.4) will be cast and either non-boranized or boranized.
Auto stop has three sensitivity settings, I run mine on lowest, makes quite a difference and still works great.
I ran as low as 280 cylinder speed in peas at engine power limit in testing this fall, the extremely erratic crop made it very difficult to properly test mind you and the odd feeder shut down did occur although nothing ever actually plugged.
150 seperator hours and the caps appear pristine. However, they were the welded assembly and boranized version 2.2.