0.4 hp Motor - Dynafile II

Models: 40352, 40353
Revised: November 20th, 2013


Use these instructions along with the tool parts page or manual.

Shut off the air supply and depress throttle lever to deplete the remaining air. Carefully disconnect the tool from the air supply hose. Remove the belt housing cover and abrasive belt. Use the Special Repair Tools designed for the disassembly and assembly of this motor.

Assembly of Motor:

Step 1

Fasten the rotor in a vise with aluminum or bronze jaws so that the rotor spindle is pointing up. Install the 01479 Spacer onto the rotor. Install .003" (~0.08 mm) shim thickness into the 01478 Front Bearing Plate.

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Step 2

Install the 02649 Bearing into the front bearing plate. Install the bearing and plate onto the rotor. Install the 04117 Adapter,
hand tight. Remove assembly from vise.

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Step 3

Use a .001" (~0.3 mm) thick feeler gauge to check clearance between the front bearing plate and the front of the rotor. Push down on the bearing plate to take movement out of the bearing. The clearance should be .001"-.0015" (~0.3 - 0.4 mm).

Notice: If the clearance needs further adjustment repeat steps 2-3. Add or remove shims as required.

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Step 4

Once the correct clearance is achieved, fasten rotor in vise and tighten the 04117 Adapter. (T to 17 N•m/~150 in. lbs).

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Step 5

Lubricate the 01480 Vanes with the 95842 Dynabrade Air Lube 10W/NR or equivalent. Install oiled vanes.

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Step 6

Use the Raised Outside Diameter of the 96242 Bearing Press Tool and the 94232 Arbor Press (#2) to install the
02696 Bearing into the 02673 Rear Bearing Plate.

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Step 7

Install the 01476 Cylinder so that the air inlet opening in the 02673 Rear Bearing Plate will line up with the air inlet opening
of the cylinder.

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Step 8

Use the Raised Inside Diameter of the 96242 Bearing Press Tool and the arbor press to install the rear bearing and plate
onto the rotor.

Notice: Carefully press the bearing and plate down until it just touches the cylinder. This will establish a close fit between the bearing plates and the cylinder.

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Step 9

Apply a small amount of clean grease to the seal of the
02696 Bearing
. Install the 02679 Shield.

Notice: The grease is used to hold the shield against
the seal of the bearing.

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Step 10

Carefully install the motor assembly into the 01546 Housing. Apply Loctite #7649 Primer or equivalent to the thread of the 01546 Housing. Apply a small amount of Loctite #567 or equivalent to the 01546 Housing.

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Step 11

Carefully fasten the 01546 Housing in the vise with aluminum or bronze jaws so that the 04117 Adapter is pointing up. Use the 50971 Lock Ring Tool and a torque wrench, or an adjustable
3 mm pin spanner wrench to fasten the 04116 Exhaust Cover onto the 01546 Housing (T to 28 N•m/~250 in. lbs).

Notice: Over tightening vise will damage housing.
Repair Collar 96461 (designed to protect the
01546 Housing) is available upon order.

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Step 12

Install air motor into the belt housing assembly.
Use a 9/64" hex key to tighten the 95311 Motor Lock Screw.

Notice: For belt housing, throttle body, and contact arm assemblies, refer to the exploded view and the additional instructions contained in the tool parts page or manual. Click Here and enter your Dynabrade Model Number
to view parts page or manual.

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Assembly of Motor Complete