Inspection; Assembly - Danfoss 51 Series Service Manual

Service Manual
U1, U2
Series 51 Two Position Controls Service Manual
Tool size and torque (continued)
Item
M22
(160, 1250)
M16, N20, NT40
N26
M18
M1 cartridge

Inspection

Clean and inspect components for damage or foreign material. Replace damaged parts as necessary.

Assembly

Refer to the illustration on the previous page.
1. Position motor with control surface up for easier assembly.
2. Install spring seat (J30), spring (J10*), and seat (J20).
3. Lubricate and install O-rings (F324) to four-way valve.
4. Lubricate and install the 4-way valve assembly (F32).
5. Lubricate and install piston (M12).
6. Using petroleum jelly to retain them, lubricate and install O-rings (G38, G42, G36), or install gasket
(G420).
7. Position control on endcap.
8. Install washers (M24) and screws (M22). Torque as shown in the table on the previous page.
9. Using a 3 mm internal hex wrench, install the plug (N26) to the control housing. Torque to 6 N•m [4
lbf•ft].
10. Lubricate the shuttle spool (NT42) and install into the cavity in the control housing.
11. Lubricate and install new O-rings (M16A, N20A, NT40A). Install plugs (M16, N20, NT40) using a 1/4
inch internal hex wrench. Torque to 37 N•m [28 lbf•ft].
12. Lubricate and install new O-ring (M18A). Install plug (M18) using a 1/8 inch internal hex wrench.
Torque to 9 N•m [7 lbf•ft].
13. Install new cartridge (M1) with pushrod. Using a thin 3/4 inch hex wrench, torque to 47 N•m [35 lbf•ft].
14. Install coil (M1) to the cartridge stem. Hand-tighten the coil nut.
11009442 • Rev CA • January 2015
Wrench size
10 mm internal hex
1/4 inch internal hex
3 mm internal hex
1/8 inch internal hex
3/4 inch hex
Torque
110 N•m [81 lbf•ft]
37 N•m [28 lbf•ft]
1. 7 N•m [2.7 lbf•ft]
78 N•m [58 lbf•ft]
47 N•m [35 lbf•ft]
41