Tuthill M-D Pneumatics 7010, Operator'S Manual, Page: 37 / 72

37
10.2.2 GEAR END ASSEMBLY
3. Place free end plate on suitable blocking with rotor
side up. Stand rotors (1) into each bore with gear
end shafts up and keyways facing in the direction
shown in Figure 18 to the right.
4. Install the gear end plate (4) over the rotor shafts
and coming to rest on top of the rotor lobes, being
careful not to damage the seals. Recheck the
location of the oil sight glass in relation to the
drive rotor before proceeding with the assembly.
Inspect lapped surface of seal mating ring to be
sure it is perfectly clean. Use a soft tissue and
cleaning agent if necessary. Place a few drops of
lubricating oil on its surface and lubricate the O-ring. Install on rotor shaft with lapped surface down.
Slot must line up with pin (300) in rotor shaft. Gently press with fingers to insure compression is taking
place and mating ring is not hung up for any reason. Top of mating ring should sit flush with rotor
shoulder when fully seated.
5. Coat the rotor shafts with an anti-seize lubricant and press the bearings (9) on the shafts. The bearing
manufacturer numbers and/or an acid dot (inner race) should be up or toward the gears. Use the tool
shown on page 44 along with a length of 3/4 - 10 × 6” threaded rod, washer (25) and nut. The use of
a hydraulic ram with a hollow center is also recommended. In this case the threaded rod will have to
be made longer.
6. Install bearing retainer plates (14) and secure with cap screws (30).
7. Check clearance between the face of the end plate and rotor lobes. Refer to Assembly Clearances table on
page 41 for correct gear end clearances. If clearances are not within specifications, recheck parts to
find cause of improper clearances before proceeding. Install keys (24) in rotor shaft keyways.
8. Lubricate shafts and keys and press drive gear (right hand helix) on drive rotor. To install driven gear,
align reference marks as shown in Figure 17 on page 35. Tap gear with mallet to start then press the
gear until seated.
NOTE
All timing gears must be used in sets as they are matched and serially
numbered.
9. Install roll pins (68), washers (25), lock tabs (59) and shaft bolts (29). Bend over lock tabs.
NOTE
These bolts are structural bolts, not standard cap screws. Therefore they
have a larger body diameter and this centers the washers and slinger. Do
not replace with standard cap screws.
10. Remove the gear end assembly from the
free end plate and turn over so the gears are
facing down on a solid surface. Place some
wood blocking on each side for support.
Place a small bead of an RTV silicone type
sealer around the periphery of the housing
[3] bores but inside the bolt pattern. Encircle
the dowel pins. Install rotor housing and
temporarily secure to end plate with two
cap screws [26] and some flat washers.
Check clearances between end of lobes and
housing using a flat bar and feeler gauges or
a depth micrometer. Refer to exploded view
for free end clearances.
Figure 18 - Keyways position
DRIVE
Keyways
Facing
Same
Direction
Figure 19 - Roller Bearing Flange