Parts List Overview:
The document provides a detailed parts list for MK-II and MK-VII controllers, including item numbers, descriptions, and quantities required. Key components include protective caps, stroke rate knobs, valve stems, diaphragms, and various screws and springs.

Assembly Instructions:
Items marked with a '+' are provided only as an assembly (P/N OS85-100). During rebuilding, items 12, 14, 16, 17, and 18 should be hand-tightened, then further tightened with a wrench for 1/8 to 1/4 turn. Over-torquing is cautioned against.

Supply Pressures:
- MK-II: 25-65 PSI (1.72-4.48 Bar)
- MK-VII: 50-90 PSI (3.44-6.20 Bar)

Application Information:
The MK-II is optimal for metering pumps with 1.25 and 2.25-inch motor cylinders and is preferred with "WIC" relays. The MK-VII is suited for pumps with 3.00 and 4.00-inch cylinders, especially when high discharge pressures require supply pressures above 65 PSI.

Valve Stem Caution:
The valve stem (item no. 4) is a control valve only and should not be used as a shut-off valve. An isolation valve should be installed upstream for shut-off purposes.

Repair Kits:
Repair kits (RK-OS42-II/VII) include items marked with a specific symbol, indicating their inclusion in the complete controller repair kit.

Contact Information:
Williams Pumps, 201 Ivyland Road, Ivyland, PA 18974-0577 USA. Phone: (215) 293-0415, Toll-Free: (800) 235-3421, Fax: (215) 293-0498, Email: [email protected]