could have resulted from improper installation of bearings.
3. Heat the right engine case first, preferably in an oven or on an
electric stove for about 10 minutes, or until the case
temperature reaches 2500 to 3000 F. If a stove is not available, you may heat the cases with a torch. If you do so, it is important to keep the torch moving to avoid concentrating the flame on one area, and to heat the whole case evenly. Do not overheat the cases, as they may distort after reaching a certain temperature. Even if you are replacing only one bearing, heat the whole case evenly, not just the area around that bearing, to prevent warpage.
4. When the case has reached the desired temperature, turn it so that the inside of the case is facing upward. Hold the new bearing by putting your index finger into the center of the bearing, and your thumb on the outer edge of the inner race. With the bearing at room temperature or less, start it into the bearing boss (Fig. 78). Push it gently downward until you hear it hit the bottom of the boss. The bearing is now in place.