Thanks for the information on the 1560 and later. As for chest thumping, Dawn also makes Curvetine II replacement closing wheels for the 750 drill. For Version 1 ours have ball bearings (US made Fafnir) but are spread, not sealed bearings and are Supercap regreaseable with our purgeable CR triple lip seal running on a nylon ring. This arrangement holds up reasonably well for the original design 750's. For the version 2 750's we have a direct replacement, RH & LH threaded male shaft setup with US made Timkin tapered roller bearings and the triple lip/nylon wear ring seal arrangement. This setup holds up very well and also has the Curvetine II type closing wheel which chips in the side wall yet has a broad shoulder so it works well in FC ground as well as no till or anything in between. Also extends life of closer arm bushings since almost no added spring pressure is required in most cases.

Here's a photo:

Jim at Dawn  

(Dawn CT-II on 750 Drill WI 0506 img2351.JPG)

Dawn CT-II on 750 Drill WI 0506 img2351.JPG (30KB - 244 downloads)