This is the conclusion of our three-part series on ball bearings. In Part One, we covered Parts, Types and Bearing Removal. Part Two covered Types and Servicing, and were concluding in Part Three with Bearing Mounting and Front Wheel Bearings. Parts One and Two are posted in our web magazine, www.southernwheels.com, in the Archives section.
Never attempt to mount a bearing on a shaft that has not been wiped clean and given a light coat of oil. Dirt or chips on such a shaft would be trapped between bearing and shaft shoulder, Figure 19, and prevent complete or accurate seating.
Never pound on a bearing or apply full force with an arbor press until assured that the bearing is started straight and not misaligned. Forcing a cocked bearing as in Figure 20 distorts the inner race and may cause it to crack. Also, the extremely hard race is likely to burr or score the shaft seal.
Never apply mounting force to the bearing outer ring where the bearing is a tight fit on the shaft, as is usually the case, Figure 21. This places a heavy thrust load on the balls and races before they are seated and in the case of bearings not meant for such thrust loads, is most likely to cause serious damage.
It is always poor practice to drive a ball bearing to a seat by the method shown in Figure 22. At best the bearing is worked down the shaft by cocking it from side to side and damage may be done that will not show up until after the parts have been put into service.
An arbor press is the most satisfactory tool for mounting ball bearings. Used properly, no blows are struck and there is no danger of loosening shields or seals from this cause.
Place the bearing on two flat blocks of equal size so that they contact the inner ring of the bearing as in Figure 23. Then press shaft straight until the bearing is seated solidly against the shaft shoulder. Be sure that the blocks do not scrape or damage the threads if the shaft is threaded for a bearing lock nut.
Use of blocks that contact both rings, Figure 24, is also good practice, provided the blocks are flat and the faces parallel.
Where the distance from shaft end to bearing seat is short, a piece of pipe or tubing may be used as in Figure 25. The pipe must be clean inside and out, and the ends squared.
In cases where a press is not available, a piece of tubing may be used with a hammer as in Figure 26. A plug in the tubing and a shield outside help to prevent jarring dirt into the bearing. The hammer should be applied alternately at opposite points to avoid cocking and particular care should be taken when the bearing is started.
FRONT WHEEL BEARINGS:
1. Cups must be press fit in hub and must be seated tight against shoulders.
2. Cones must be slip fit on spindle and bores lubricated to insure creep.
3. Spindle nut must be free-running fit on threads. (Remove all burrs from threads, key slot and cotter pin holes.)
Remove inner rings, ball assemblies and grease seal. Washclean in approved solvent cleaner. Wash inside of hub with solvent. Inspect, replacing any parts necessary. Keep bearings free from dirt. Lubricate at once, as below, to prevent rusting. If a replacement, soak new seal in engine oil before installing.
Using wheel bearing grease, the type having a sodium or sodium/calcium base (unless otherwise specified in the car manufacturers lubrication chart), coat inside of hub and spindle with a film of grease not over 1/16" thick. Pack ball and separator assemblies entirely full, working grease thoroughly into all spaces and covering balls. Use no more grease than specified. Too much may cause leakage into brakes. Reassemble at once and adjust as below.
Push ring Bthrough seal until in contact with bearing. Slide hub onto spindle. Hold in place until ring Ais pushed into position.
1. Tighten adjusting nut with torque wrench to approximately 200 inch-pounds to insure that all parts are properly seated and threads are free.
2. Back off nut and re-tighten to between 45-55 inch-pounds (equivalent to approximately 5 pounds pull on a 10wrench.)
3. If cotter pin hole in spindle and slot in nut line up, insert cotter pin. Otherwise, back off adjusting nut to nearest line up of slot and hole and insert cotter pin.
CAUTION: Discoloration of balls is no cause for removal of bearing parts. It is only a surface color in no way detrimental to bearing life.
With proper care, our carsbearings can last indefinitely, providing years of trouble-free service. I hope you have enjoyed the series. See you next month, and keep 'em driving!