Bearing Installation

1. When installing a bearing in a housing, pressure must be applied to the outer bearing race (Figure

68). When installing a bearing on a shaft, pressure must be applied to the inner bearing race (Figure

2. When installing a bearing as described in Step 1, some type of driver will be required. Never strike the bearing directly with a hammer or the bearing will be damaged. When installing a bearing, a piece of pipe or a socket with an outer diameter that matches

Figure 71, the balls will push against the outer bearing track and damage it.

Before hea procedure t the cases th water. Riru required to other cherr

Shrink Fit

1. Installing a bearing over a shaft: When a tight fit is required, the bearing inside diameter will be smaller than the shaft. In this case, driving the bearing on the shaft using normal methods may cause bearing damage. Instead, the bearing should be heated before installation. Note the following:

a. Secure the shaft so that it can be ready for bearing installation.

b. Clean the bearing surface on the shaft of all residue. Remove burrs with a file or sandpaper.

c. Fill a suitable pot or beaker with clean mineral oil. Place a thermometer (rated higher than 248° F [120° C]) in the oil. Support the thermometer so that it does not rest on the bottom or side of the pot.

d. Remove the bearing from its wrapper and secure it with a piece of heavy wire bent to hold

The housir of about 21

plate. An e the proper water on ti and evapo correct. Hi





Shaft the bearing race will be required. Figure 70 shows the correct way to use a socket and hammer when installing a bearing over a shaft.

3. Step 1 describes how to install a bearing in a case e. half and over a shaft. However, when installing a bearing over a shaft and into a housing at the same time, a snug fit will be required for both outer and inner bearing races. In this situation, a spacer must be installed underneath the driver tool so that pressure is applied evenly across both races. See Figure 71. If the outer race is not supported as shown in it in the pot. Hang the bearing in the pot so'Ji quickly when it does not touch the bottom or sides of the pt ing is installs

2. Installing a bee

Turn the heat on and monitor the thermomeit I generally installed When the oil temperature rises to appm |erenCe fit. Drivir mately 248° F (120° C), remove the beara using normal metl from the pot and quickly install it. If necessar cause bearing dan place a socket on the inner bearing race andfc ^ heated before the bearing into place. As the bearing chills,! following: will tighten on the shaft so you must wcl the bearing in the pot so thai le bottom or sides of the pol id monitor the thermometer, iperature rises to approxi-0° C), remove the bearing lickly install it. If necessary, | e inner bearing race and tap ce. As the bearing chills, ii shaft so you must work





. Socket j- Bearing quickly when installing it. Make sure the bearing is installed all the way.

2. Installing a bearing in a housing: Bearings are generally installed in a housing with a slight interference fit. Driving the bearing into the housing using normal methods may damage the housing or cause bearing damage. Instead, the housing should be heated before the bearing is installed. Note the following:

CAUTION Before heating the crankcases in this procedure to remove the bearings, wash the cases thoroughly with detergent and water. Rinse and rewash the cases as required to remove all traces of oil and other chemical deposits.

a. The housing must be heated to a temperature of about 212° F (100° C) in an oven or on a hot plate. An easy way to check to see that it is at the proper temperature is to drop tiny drops of water on the case as it heats up; if they sizzle and evaporate immediately, the temperature is correct. Heat only one housing at a time.

CAUTION Do not heat the housing with a torch (propane or acetylene). Never bring a flame into contact with the bearing or housing. The direct heat will destroy the case hardening of the bearing and will likely warp the housing.

b. Remove the housing from the oven or hot plate and hold onto the housing with a kitchen pot holder, heavy gloves or heavy shop cloths—it is hot.

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