SHIELD-HEAT 2737569 - Caterpillar

Illustration 3 g00275111
Pinion Shaft Spline (backlash measurement) (B) Distance of dial indicator from the centerline of the pinion.
Measure the backlash between bevel gear (17) and pinion shaft (13) on the pinion shaft spline. To measure the backlash, place a dial indicator tangent to the spline on a flat of a drive shaft yoke or a spline adapter. Make sure that the yoke or the spline adapter is tight to the spline.
The following table lists examples of backlash at the pinion shaft. The table shows the different distances from the centerline of the pinion to the dial indicator:
Table 1
Examples of Backlash at Pinion Shaft    
Dimension (B)     Nominal Backlash     Maximum Backlash     Minimum Backlash    
50 mm (2 inch)    
0.30 mm (.012 inch)    
0.40 mm (.016 inch)    
0.18 mm (.007 inch)    
100 mm (4 inch)    
0.58 mm (.023 inch)    
0.80 mm (.032 inch)    
0.35 mm (.014 inch)    
150 mm (6 inch)    
0.87 mm (.035 inch)    
1.20 mm (.048 inch)    
0.53 mm (.021 inch)    
200 mm (8 inch)    
1.15 mm (.046 inch)    
1.60 mm (.064 inch)    
0.70 mm (.028 inch)    If the backlash does not meet specifications, loosen one adjusting nut and tighten the opposite adjusting nut by the same amount. This will maintain the bearing preload.Check the Pinion and Bevel Gear Tooth Contact
After the differential backlash adjustments and the pinion preload adjustments have been made, check the tooth contact between pinion shaft (13) and bevel gear (17). Perform the following procedure:
Coat three or four adjacent teeth of bevel gear (17) with a rouge compound.
Rotate pinion shaft (13) for several revolutions in one direction. Then rotate pinion shaft (13) for several revolutions in the opposite direction. Then turn the pinion shaft in one direction until the marked teeth can be viewed.
Illustration 4 g00103470
The correct area of tooth contact begins near the inside end of the teeth of bevel gear (17). The correct area extends 25 to 50 percent of the tooth length. See Illustration 4 for an example of the correct area of tooth contact.
Illustration 5 g00103471
If the tooth contact looks like the marks in Illustration 5, remove some of shims (26) and check the backlash again. Repeat the procedure under Step 1.
Illustration 6 g00508806
If the tooth contact looks like the marks in Illustration 6, add some of shims (26) and check the backlash again. Repeat the procedure under Step 1.Note: Always make sure that the backlash adjustment is correct before an adjustment is made to the area of tooth contact. To achieve the correct adjustments, the backlash and the tooth contact may need to be adjusted several times. Always remember that a change to gear clearance (backlash) will also change the gear contact and vice versa.
After adjustments are made, remove the rouge compound from the gears.
Illustration 7 g00572825
(2) Bolt. (3) Adjusting nut.
Install bolt (2) and a lock tab washer in adjusting nut (3). Tighten bolt (2) to 12 3 N m