Dynabrade 10787, Safety, Operation And Maintenance

Assembly/Disassembly Instructions

Important: The Manufacturing Warranty is void if the tool is disassembled before the warranty expires by anyone other than a Dynabrade

®

Approved Repair Technician. Notice: 

A 

98224

Motor Tune-Up Kit is available. Also, the special repair tooling referred to in these instructions can be ordered

through your Dynabrade

®

Distributor. Please refer to this tool manual for correct part number identification.

Important: Always follow these steps before servicing any part of this air tool.

1. Shut off the air supply and then depress throttle lever to dissipate the remaining air.
2. Carefully disconnect the tool from the air supply hose.

Note: 

Use a wrench to hold the air tool inlet bushing stationary when removing the air supply connection.

Orbital Head Disassembly:

1.

Slide 

61394

Switch Shaft to the random (lock) position.  Use the 

95823

21mm wrench to hold the orbital head in position and removed the 

96188

Screw

with the 

95049

3/16" hex key.

2.

Hold the 

18552

Housing in a vise with bronze or aluminum jaws so the orbital head assembly is facing up.

3.

Apply localized heat to the three 

95235

Screws and use a 9/64" hex key to remove these.

4.

Apply localized heat to the 

57069

Balancer Shaft and remove the shaft along with the 

56052

Bearing.

5.

Use the 

96346

2" Bearing Separator and the 

96232

#2 Arbor Press to remove the 

56052

Bearing from the 

57069

Balancer Shaft.

6.

Apply localized heat to 

61398

Locking Pin Bushing and use 

96364

Slotted screwdriver to remove.

7.

Remove 

61935

Switch Spring, 

61393

Pin, 

61397

Spring, and 

61396

Locking Pin Insert.

8.

Remove 

61394

Switch Shaft from Orbital Head Housing.

9.

Use the 

95823

21mm Wrench to remove the orbital head from the spindle.

Orbital Head Disassembly Complete.

Motor Disassembly:

1.

Hold the 

18552

Housing in a vise with bronze or aluminum jaws so that the 

18579 

Valve Housing is pointing up.

2.

Pull the 

18061

Grip off the 

18579

Valve Housing. 

Note

: A “Hot Air Gun” can be used to warm the 

18601

Grip, making it more flexible.

3.

Use the 

95331

(4mm) Hex Key to remove the 

18580

Screws (4), 

18559

Washers (4), 

18579

Housing, 

18578

Gasket, 

18577

Spacer, 

18574

O-Ring

and 

18576

Gasket.

4.

Carefully slide the air motor out of the 

18552

Housing. 

Note

: A “Hot Air Gun” can be used to warm and expand the 

18552

Housing.

5.

Use the 

96343

Retaining Ring Pliers to remove the 

18567

Retaining Ring.

6.

Fasten the 

96346

, (2") Bearing Separator carefully between the 

18573

Rear Bearing Plate and the 

18571

Cylinder and place the separator on the table 

of the 

96232

, (#2) Arbor Press so that the 

18594

Pinion Gear is pointing down.

7.

Use a 3/16" dia. flat end drive punch as a press tool to push the 

18595

Rotor out of the 

18555

Bearing.

8.

Use the 

96213

Bearing Removal Tool and the arbor press to push the 

18555

Bearing out of the 

18573

Rear Bearing Plate.

9.

Fasten the bearing separator around the flange of the 

18594

Pinion Gear so that the flat side of the separator is against the 

18568

Bearing. With a 

downward motion, strike the flat side of the separator against the table of the arbor press several times. The 

18568

Bearing will slide out of the 

18569

Front Bearing Plate.

10.

Use a 3/16" dia. flat end drive punch as a press tool and the arbor press to push the 

18594

Pinion Gear out of the 

18568

Bearing.

11.

Use a 3/16" dia. flat end drive punch as a press tool and the arbor press to push the 

18595

Rotor out of the front 

18555

Bearing. Use the 

96213

Bearing 

Removal Tool and the arbor press to push the 

18555

Bearing out of the 

18569

Front Bearing Plate.

Motor Disassembly Complete.

Right Angle Gear Disassembly:

1.

Use the 

95331

(4mm) Hex Key to remove the 

18560

Screws (4), and 

18559

Washers (4).

2.

Fasten the 

96346

Bearing Separator under the 

18555

Bearing and use a 3/16" dia. flat end drive punch and the 

96232

, (#2) Arbor Press to push the 

bearing from the spindle.

3.

Use the 

96343

Retaining Ring Pliers to remove the 

18556

Retaining Ring, 

18557

Wave Washer, 

18593

Bevel Gear, and 

18563

Key.

4.

Use the 

96343

Retaining Ring Pliers to remove the 

18562

Retaining Ring, and pull the spindle along with the 

18561

Bearing out of the

18902

Spindle Cap.

5.

Place the 

18561

Bearing on the tool plate of the arbor press and push the spindle out of the bearing.

Right-Angle Gear Disassembly Complete.

Motor Assembly:

1.

Use the raised outer portion of the 

96240

Bearing Press Tool to install the 

18555

Bearing into the 

18569

Front Bearing Plate.

Note

: Use the 

96232

(#2) Arbor Press.

2.

Position the 

18595

Rotor on the 

96231

Tool Plate of the 

96232

(#2) Arbor Press so that the rear portion of the rotor body is flat on the tool plate and the 

spline end is pointing up. Use the 

18571

Cylinder as a jig. Place the cylinder over the rotor so that it is also setting on the tool plate. Slip the front 

bearing/plate assembly over the spline end of the rotor and use the raised center portion of the 

96240

Bearing Press Tool to install the front 

bearing/plate assembly onto the 

18595

Rotor. 

Note

: Use approximately 3 lbs. (1364g.) of force. Remove the rotor with the bearing/plate assembly from 

the arbor press. Use a .001" (.03mm) thick feeler gage to check the fit of the bearing plate to the face of the rotor. The clearance between the bearing 
plate and the face of the rotor should be .001" to .0015" (.03 -.04mm).

3.

Place the 

18568

Bearing flat on the tool plate of the arbor press and install the 

18594

Pinion Gear into the inner race of the bearing.

4.

Place the 

18569

Front Bearing Plate flat on the tool plate of the arbor press so that the rotor is hanging down. Set the 

18568

Bearing on the opening of 

the 

18569

Front Bearing Plate so that the pinion gear is pointing up. Place one end of the 

18571

Cylinder against the outer race of the 

18568

Bearing 

and using the cylinder as a press tool, push the 

18568

Bearing into the front bearing plate.

5.

Apply a small amount of the 

95842

Dynabrade Air Lube (10W/NR or equivalent) to the 

18570

Blades (4) and install them into the 

18595

Rotor.

6.

Place the 

18573

Rear Bearing Plate flat on the tool plate of the arbor press and use the raised outer portion of the 

96240

Bearing Press Tool to install 

the 

18555

Bearing into the rear bearing plate.

(continued on next page)

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