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How To Use This Manual

This manual applies to standard Falk Type NRT backstops.

This manual provides detailed instructions on oil seal

replacement. Use the following Table of Contents to locate

required information.

Table of Contents

Oil Seal Replacement (Cast Iron End Covers). . . . . . . . . . . 1-2
Backstop Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Backstop Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Seal Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Backstop Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Backstop Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Oil Seal Replacement (Fabricated Steel End Covers). . . . . . 2-3

CAREFULLY FOLLOW THE INSTRUCTIONS IN THIS

MANUAL FOR OPTIMUM PERFORMANCE AND TROUBLE

FREE SERVICE.

Introduction

This manual covers oil seal replacement for both cast iron and 

fabricated steel end covers. See Page 2 for oil seal

replacement for backstops with fabricated steel end covers.

BACKSTOP SEAL REPLACEMENT — 

For Backstops 

with Cast Iron End Covers, See Figure 3, Page2.

CAUTION:

 Remove all external loads from drive before

servicing drive or accessories. Do not damage cam or hub

face: new seals will leak if seal contacting surface is marred.

Do not use abrasive material on seal contacting surface.

Required Equipment

In addition to standard mechanic’s tools, the following

equipment is required: hoist, sling, torque wrench, dial

indicator with stand or depth micrometer and puller.

CAUTION:

 Do not attempt to service or remove backstop before 

removing load. When removing backstop from shaft, do not
apply heat to the backstop. Apply axial force to the hub of the

backstop only.

Backstop Removal

1. Drain and discard lubricant in an environmentally safe

method.

2. Remove oil sight gauge and breather assembly and insert

pipe plugs in cover holes.

3. Remove torque arm. Refer to Figure 1 for proper method

of supporting and lifting.

4. Reassemble torque arm pins in backstop and lock in place

with cotter pins for lifting.

5. If the backstop is furnished with a axial retaining collar(s),

loosen set screws and mounting bolts and remove collar.

Remove burrs on shaft caused by set screws.

6. Remove backstop from shaft. Apply force to the inner cam

of the backstop only. (Figure 1)

7. Thoroughly clean exterior of backstop with clean solvent to

prevent dirt from falling into the backstop when disassembling.

8. Position backstop on clean work surface with bore vertical.

Support lower end cover with wood blocks. (Figure 2)

Backstop Disassembly

9. Remove upper end cover bolts and end cover using

eyebolts as jackscrews for separation and lifting. (Figure 2)
Do not remove cam, bearings, stop lugs, springs or roller

cage assembly; removal will void applicable warranties.

10. Remove and note number of gaskets; discard old gaskets.
11. Clean outer race gasket area.
12. Remove grease from around the seals if the grease purge

feature has been used. Drive out seals and remove sealing
compound from mounting surface. Clean entire end cover

with clean non-flammable solvent and wipe dry.

Rexnord Industries, LLC, Geared Products, P.O. Box 492, Zip 53201-0492

568-130

3001 W. Canal St., Zip 53208-4200, Milwaukee, WI USA Telephone : 414-342-3131

February 2009

Fax: 414-937-4359 e-mail: [email protected] web: www.rexnord.com

Supersedes 11-01

Falk™ Horizontal Shaft Backstops 

 Oil Seal Replacement

Type NRT 

 Sizes 70-180, 1070-1185

(Page 1 of 3)

COTTER PIN

TORQUE ARM PIN

END COVER

CAM OR HUB FACE-

PUSH ON THIS FACE

WHEN INSTALLING

BACKSTOP ON SHAFT 

BALANCE

POINT

NYLON

SLING

TORQUE ARM

CLAMPS TO PREVENT

SLING FROM SLIPPING

OFF "I" BEAM

NYLON SLING

Figure 1

LIFT

EYE BOLT IN

 

JACKSCREW HOLES

END COVER

INNER CAM

BEARING

OUTER RACE

Figure 2

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