Usage:
Drive (13) and Driven (14) Gear Assemblies
Inspect shafts for roughness in the bearing and sealing areas. Measure for wear. Minimum acceptable .4998" in "D", .7492" in "H" and .9365" in "M".
surface finish maximum.
Inspect keyway, keys or splines for damage or excessive wear.
Inspect the gear end faces, outside diameter and teeth for roughness and score marks. The O.D. of the "D" gears must be 1.2395" minimum, "H" gears must be 1.7140" minimum and the "M" gears 2.1047" minimum. For minimum gear widths see Table (I).
Be sure snap rings are secure; break any sharp edges on the sides of the gears.
Gears and shafts are available only as assemblies. One gear assembly may be replaced separately if the other is in good condition.
Depress the seal pressurizing valve (15), (16), (17) and (18) in the driven gear assembly to be sure there is some resistance but movement is free. ("H" and "M" only.)
Front Cover (5) and Back Cover (21) Assemblies
If any bearing bore diameter exceeds .5015" in the "D" Series, .7518" in the "H" Series, or .9394" in the "M" Series, the cover should be discarded. Bearings are not supplied separately.
Replace the shaft seal (1) only if it shows excessive wear or cracking.
Check all internal threads for damage.
Bearings must be below the cover faces and show no signs of contact with snap rings on gear shafts.
If bearings are scored, rough, or show signs of heat discoloration, the cover assemblies should be replaced.
Center Section (12)
Inspect the wall of gear bore diameters for excessive wear or score marks. The center section gear bores will show signs of wear on the inlet side of the pump. A wear ridge will develop at the end of the gear bore where the thrust plate is located. This wear ridge should not exceed 1/32". Lightly lap the faces to remove any nicks or burrs. Do not break inside edges.
Wear Plate (10) and Thrust Plate (22)
Inspect bronze wear surfaces for excessive roughness or heat discoloration. If wear ridges exceed .0005", discard and replace.
General
The following parts should be replaced at every major overhaul: Wear Plate (10), Thrust Plate (22), Fiber Heat Shield (9), Paper Gasket (8), "V" Seal (6), and "O" Rings (11). The shaft seal (1) should be replaced only when necessary.
