Dynabrade Grinder Series User Manual

Disassembly, Assembly Instructions - 2.8 hp Grinder/Sander Series:
Ø 7" & 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.

Dynabrade Grinder Series Specifications

General

Brand	Dynabrade
Model	Grinder Series
Category	Power Tool
Language	English

Summary

Motor Disassembly Steps

Step 1: Secure Housing and Remove Screws

Fasten housing in vise and remove screws using a 4mm hex key.

Step 2: Remove Throttle Handle Assembly

Remove throttle handle assembly, including spacer, spring, and gasket.

Step 3: Remove Governor Chamber

Detach the governor chamber from the housing.

Step 4: Loosen Motor Assembly

Use soft-faced hammer to dislodge motor assembly from housing.

Step 5: Remove Governor Assembly

Unscrew governor assembly from pinion gear using slot-blade screwdriver.

Step 6: Separate Motor from Cylinder

Use bearing separator and arbor press to push rotor out of bearing.

Step 7: Remove Bearing from End Plate

Use external ring pliers to remove bearing from rear end plate.

Step 8: Remove Rotor Vanes

Extract vanes from the rotor.

Step 9: Remove Pinion Gear

Unscrew pinion gear using a 14mm wrench.

Step 10: Remove Front End Plate & Spacer

Remove front end plate, bearing, and spacer.

Motor Assembly Procedures

Step 1: Prepare Rotor for Assembly

Fasten rotor in vise and install spacer onto it.

Step 2: Assemble Front End Plate Components

Install shim, O-ring, and bearing into front end plate.

Step 3: Attach Plate to Rotor

Apply Loctite #243 and install bearing and plate onto rotor.

Step 4: Install and Torque Pinion Gear

Fasten pinion gear using 14mm wrench and torque to specifications.

Step 5: Check Rotor/Plate Clearance

Check and adjust rotor/plate clearance using feeler gauges and shims.

Step 6: Install Rotor Vanes

Apply lube to vanes and install them into the rotor.

Step 7: Install Cylinder and Rear End Plate

Position cylinder and rear end plate, aligning air inlet openings.

Step 8: Install Rear End Plate Components

Install rear end plate and position bearing onto assembly.

Step 9: Install Rear Bearing

Use bearing press tool and arbor press to install rear bearing.

Step 10: Install Governor Assembly

Apply Loctite #243 to governor threads and install assembly.

Motor Installation into Housing

Step 1: Install Governor Chamber

Fasten housing, slide motor assembly in, and install governor chamber with O-ring.

Step 2: Install Throttle Handle Components

Install gasket, motor spring, spacer, and throttle handle assembly.

Step 3: Secure Motor Assembly

Use 4mm hex key to fasten screws, torquing to specifications.

Gear Disassembly Procedures

Step 1: Remove Lock Ring

Use adjustable pin spanner to remove lock ring counterclockwise.

Step 2: Remove Work Spindle Assembly

Detach work spindle assembly from housing.

Step 3: Remove Wave Disc

Use tweezers to extract wave disc.

Step 4: Remove Bearing from Spindle

Use bearing separator and arbor press to remove bearing from spindle.

Step 5: Separate Spindle from Gear

Push spindle from bearing and bevel gear using hydraulic press.

Gear Assembly Procedures

Step 1: Install Bearing on Spindle

Use press to install bearing onto spindle until fully seated.

Step 2: Install Bevel Gear

Use press to install bevel gear onto spindle until fully seated.

Step 3: Install Second Bearing

Use bearing press tool to install bearing until level with spindle top.

Step 4: Adjust Gear Backlash

Install spindle, check and adjust backlash, then secure lock ring.

Step 5: Install Wave Disc

Insert wave disc into housing.

Step 6: Apply Grease and Install Assembly

Apply grease to housing cavities/pinion gear, install shims and spindle assembly.

Step 7: Install Lock Ring

Apply Loctite #567 to lock ring threads and install, torquing to specs.

Final Assembly and Operation

Lubrication Recommendations

Details motor oiling frequency and gear grease replacement intervals.

Operational Checks

Refer to manual for RPM checks and accessory installation.

Install Guard and Flange

Fasten guard securely using five screws, torquing to specifications.