Dynabrade 51520 Quick start guide

Disassembly Instructions - Wet, Stone Polisher
Model: 51520
Important: Use these instructions along with tool parts page or manual.
Notice:
Shut off air supply and depress throttle lever to deplete air.
Disconnect tool from air supply hose.
Shut off water supply faucet and disconnect.
Remove all accessories (abrasive product, backup disc, and flanges) from tool.
Motor Disassembly:
1. Push against collar of 96227 Fitting and pull 95579 Water Line tubing from fitting.

2. Install 95492 Screws (5/16"-18 SHC) in two handle bosses on housing.
Fasten 95492 Screws in vise to hold tool with 51546 Valve Body pointing up.
Use a 3 mm hex key to remove 96296, 95916 Screws along with 01211 Lock
Washers. Turn counterclockwise.
Carefully remove valve body assembly, spacers, gaskets and o-rings.
Set aside and save parts.
3 mm hex key

3. Remove motor form housing.

4. Fasten 96346 Bearing Separator (2") around 01028 Cylinder.
Place assembly in 96232 Arbor Press (#2) with pinion pointing down.
Use a Ø 1/4" drive punch to push 02373 Rotor out of 02649 Bearing.
96346 Bearing Separator

5. NOTICE: In the same way, use bearing separator, arbor press and 96213 Bearing
Removal Tool, to remove 02649 Bearing from 01732 Rear Bearing Plate.
Save parts.
96213 Bearing Removal Tool

6. Fasten 02373 Rotor in vise with aluminum or bronze jaws, with pinion pointing up.
Use an adjustable hook spanner wrench to remove 51513 Pinion Gear. Turn
counterclockwise.
Remove front bearing, plate, spacer and shims.
Motor disassembly completed.
Clean and inspect parts for wear or damage. Save and reuse good parts.

Right Angle Gear Disassembly:
1. Install 95492 Screws (5/16"-18 SHC) in two handle bosses on housing.
Fasten 51545 Housing in vise with spindle pointing up.
Use a HEAT GUN to warm housing.
Use an adjustable pin spanner wrench to remove 51551 Spindle Retainer. Turn
clockwise. Left Hand Thread.
HEAT
GUN

2. Loosen vise and remove housing.
Remove 96584 O-Ring.
Remove spindle and bevel gear assembly.
Remove 98243 Wave Spring.

3. Fasten 96346 Bearing Separator (2") under 02057 Bearing.
Place assembly in 96232 Arbor Press (#2) with threaded end of spindle pointing
down.
Use a Ø 3/16" drive punch to push spindle out of 02057 Bearing.
NOTICE: In the same way, use bearing separator and arbor press to remove
51514 Gear and 02685 Bearing.
IMPORTANT: Inspect 95913 Seals and 51550 Spindle. Replace worn parts!
NOTICE: Loctite #380 is used to retain 95913 Seals in 51551 Spindle Retainer.
Acetone can be used to soften adhesive and remove seals. SEE: Right Angle
Gear Assembly.
Right angle gear disassembly completed.
Clean and inspect all parts for wear or damage. Only reuse good parts.
Notice: To disassemble and assemble muffler and valve components, refer to
parts page or tool manual and follow exploded view instructions.
96346 Bearing Separator

Assembly Instructions - Wet, Stone Polisher
Motor Assembly:
1. Install 01010 Spacer onto rotor.
Install .003" (~0.08 mm) shim thickness into 02375 Front Bearing Plate.
Install 01007 Bearing into front bearing plate.
Install bearing and plate onto rotor.

2. Install 51513 Pinion Gear hand tight.
Place end of pinion gear against a solid surface. Push down on front bearing
plate.
Use a .001" (~0.03 mm) thick feeler gauge to check clearance between rotor
and plate.
Notice: Clearance should be .001"-.0015" (~0.03-0.04 mm). If rotor/plate
clearance needs further adjustment, repeat steps 1 and 2. Remove or add shims
as necessary.
.001"-.0015"
(~0.03-0.04 mm)

3. Fasten 02373 Rotor in vise with aluminum or bronze jaws.
Use an adjustable hook spanner wrench to tighten 51513 Pinion Gear.
Torque to 17 N•m/~150 lbs. in.
Torque to 17 N•m/~150 lbs. in.

4. Apply 95842 Dynabrade Air Lube or equivalent to 01185 Vanes.
Install vanes into rotor.
OIL

5. Use RAISED OUTSIDE DIAMETER of 96240 Bearing Press Tool to install 02649
Bearing into 01732 Rear Bearing Plate.
96240 Bearing Press Tool

6. Use RAISED INSIDE DIAMETER of 96240 Bearing Press Tool and arbor press to
install 02649 Bearing and rear bearing plate onto rotor.
Carefully press bearing and plate down until plate just touches cylinder. This
will produce a close fit between bearing plates and cylinder.
JUST TOUCH
96240 Bearing Press Tool

7. Use a HEAT GUN to warm and expand housing.
HEAT
GUN

8. Use 51560 Spacer as a guide to position and install air motor.
51560 Spacer

9. Install 01024 O-Ring and 51552 Gasket.
01024 O-Ring
51552 Gasket

10. Install 51560 Spacer, 51569 Spacer & 01024 O-Ring, 51113 Gasket & 51568
Spacer.
51569 Spacer
01024 O-Ring
51113 Gasket
51568 Spacer
51560 Spacer •

11. Install 51546 Valve Body assembly.
Use 3 mm hex key to install 96296 & 95916 Screws with 01211 Lock Washers.
Torque to 4.5 N•m/~40 lbs. in.
Important: Check operation of air motor.
Connect tool air inlet, to an air supply that delivers a maximum of 90 PSIG (6.2
Bar) operating air pressure.
If motor operates smooth and regular continue with right angle gear assembly.
If motor does not operate or performance is erratic, disconnect tool and correct
problem before continuing.
Motor assembly completed.
Torque to 4.5 N•m/~40 lbs. in.