Dynabrade Grinder Series User manual

Disassembly, Assembly Instructions - 2.8 hp Grinder/Sander Series:
Ø7"& 9", Right Angle
Models: Use for all models.
Important: Disconnect from the air supply.
Notice: Use these instructions along with the specific tool manual for each model.
To avoid damage, use the proper repair tools designed for motor disassembly and
assembly.
! Remove any flanges, abrasive, back-up disc or guard.
Motor Disassembly: (Tutorial shows tool with 54951 Spindle. - Applies to all models.)
1. Fasten housing in vise (bronze or aluminum jaws) with throttle handle pointing up.
• Use a 4mm hex key to remove 95720 Screws (4). Turn counterclockwise.

2. Remove throttle handle assembly.
! Remove 54961 Spacer, 54960 Motor Spring, and 54958 Gasket.
54958 Gasket
54960 Motor Spring
54961 Spacer

3. Remove 54953 Governor Chamber.

4. Use soft-faced hammer to knock motor assembly loose from housing and remove.

5. Carefully, fasten pinion gear in vise (bronze or aluminum jaws).
! Use a slot-blade screwdriver to remove governor assembly. Turn clockwise.
Left Hand Thread

6. Fasten 96346 Bearing Separator (2") around 54905 Cylinder. Place separator and
motor in 96232 Arbor Press (#2) with pinion gear pointing down.
! Use a Ø ⅛" flat-end drive punch to push rotor out of 54907 Bearing.
96232 Arbor Press
96346 Bearing Separator

7. Use external ring pliers to remove 54907 Bearing from 54880 Rear End Plate.

8. Remove 54904 Vanes from 54903 Rotor.

9. Use 95262 Wrench (14mm) to remove pinion gear. Turn counterclockwise.
14MM

10. Remove; 54900 Bearing, 54901 Front End Plate along with shims and 54902
Spacer.
Motor disassembly completed.
Clean and inspect parts. Replace all parts that are worn or damaged.

Motor Assembly:
1. Fasten 54903 Rotor in vise (bronze or aluminum jaws), with spindle pointing up.
! Install 54902 Spacer onto rotor.

2. Install 54909 Shim into 54901 Front End Plate.
! Select .003" (~0.08 mm) shim thickness from 94910 Shim Pack and install into
front end plate.
! Install 01787 O- Ring into outside diameter groove of plate.
! Install 54900 Bearing all the way into plate.
Shims
54909 Shim
01787 O-Ring
54900 Bearing

3. Install bearing and plate onto rotor.
! Apply a small amount of Loctite #243 to spindle threads of rotor.
Loctite #243

4. Use 14mm Wrench (or thin crowfoot) to fasten pinion gear. Turn clockwise.
! Torque to: 17 N•m/~150 lbs. in.
14mm
Torque to: 17 N•m/~150 lbs. in.

5. Carefully, fasten pinion gear in vise (bronze or aluminum jaws). Push the front-end
plate away from the rotor. Check clearance between the rotor and plate.
! Use a .001" (~0.03 mm) thick feeler gauge.
! Notice: The clearance should be .001"-.0015" (~0.03 to ~0.04 mm).
! If rotor/plate clearance requires further adjustment, repeat steps 2 to 5.
Remove or add shims as required.
.001"-.0015"
(~0.03-0.04 mm)

6. Apply 95842 Dynabrade Air Lube 10W/NR or equivalent to 54904 Vanes and install.
OIL

7. Install 54905 Cylinder and rear end plate so that air inlet openings line up.

8. Install 54880 Rear End Plate with related components.
• Position 54907 Bearing on assembly.
54880 Rear End Plate
96773 O-Ring
96772 Wave Washer
96779 O-Ring

9. Use the RAISED INSIDE DIAMETER of 96419 Bearing Press Tool, and the arbor
press to install rear bearing.
! Press bearing flush with top of plate.
This will produce ~12 Lbs. load between both bearing plates and the cylinder.
96419

10. Carefully, fasten pinion gear in vise (bronze or aluminum jaws).
• Apply a small amount of Loctite #243 to threads of governor.
• Use a slot-blade torque-driver to install governor assembly.
• Left Hand Thread. Turn counterclockwise. Torque to: 1.4 N•m/~12 lbs. in.
Motor assembly completed.
Left Hand Thread. Turn counterclockwise. Torque to: 1.4 N•m/~12 lbs. in.
54998 Governor Assembly
#243 Loctite