Meritor TM Series Service Manual page 25

4 Hub Service
THE SEAL MUST BE DISCARDED. NEVER RE-USE AN OIL SEAL
AFTER THE HUB HAS BEEN DISMOUNTED FROM THE AXLE
SPINDLE.
Remove the inner bearing cone and place it in a clean area.
Identify the bearing cone clearly to ensure that it is refitted to its
original position in the hub.
Two types of seal may be found on Meritor HVS TM axles:
1. Unitised seal – NO WEAR SLEEVE FITTED.
2. Grease seal with wear sleeve fitted to axle.
NOTE
: From July 1980, all Meritor HVS axles are fitted with
unitized seals and therefore NO wear sleeves are required.
Meritor HVS specifies Unitized seals, which do not require wear
sleeves.
NOTE
Unitized seals are directly interchangeable with the older
grease seal after removal of the wear sleeve.
If the hub incorporated an early seal arrangement with wear
sleeve, remove the wear sleeve carefully by tapping the sleeve
with a ball hammer, or using a suitable slide hammer. Take care
not to damage the spindle.
NOTE
Prior to installing any seal in the hub make certain that
the seal bore is free of any nicks, gouges or other damage. This
will prevent any leakage around the seal's outer diameter.
CHECK GREASE CONDITION
If the grease within the bearing is clean and does not appear burnt
there should be no necessity to totally clean down the assembly.
Check the hub cavity for any grease contamination caused during
hub removal from the spindle. Any contamination must be
removed or if this is excessive a complete hub clean down must
be carried out.
CLEANING OF HUB
Wipe clean the hub cavity removing all the old grease and any
contamination.
CAUTION:
Ensure any grease removed from the
assembly/components, or contaminated cloth, is
disposed of in accordance with local environmental
regulations.
Meritor HVS TM Series Axle
25
INSPECT BEARINGS
Check both bearings, cones and raceways for:
• Cage damage
• Corrosion
• Roller and raceway damage or pitting
• Metallic debris or flaking Bearing cup security - Ensure both
bearing cups are well secured in the hub, by checking they are
fully seated within the hub bore, and with a good grip of the cups
try to rotate them. If any movement of the cups is detected then
the hub will have to be replaced. Do not attempt to fit new
bearings into a hub with worn bores.
If any of the above defects are evident the complete bearing (cup
and cone) MUST be replaced.
NOTE:
It is advisable to replace with a complete new hub and
bearing assembly which is available from Meritor Aftermarket
Distributors.
INDIVIDUAL BEARING REPLACEMENT PROCEDURE
Drift out the bearing cup from the hub ensuring that the bearing
bore within the hub is not damaged.
NOTE
: Four cut-outs in the casting allow a soft steel drift to be
used to remove inner cup, using each cut-out alternately. The
bearing will be removed with relative ease and without damage.
Hardened steel drifts or brass bars must not be used.
BEARING CUP REFITMENT
Ensure the hub cavity is clean and free from visual damage,
debris, burrs or any oxidation.
CAUTION
: The bearing 'Cups' and 'Cones' are clearly
marked by manufacturer type for identification. Never
assemble a bearing using a 'Cup' from one manufacturer with a
'Cone' from a different manufacturer. Always check the bearing
components are from the same manufacturer before assembly
continues.
CAUTION
: ALWAYS USE GENUINE MERITOR
BEARINGS - STANDARD ISO BEARINGS CANNOT BE
USED.