Specifications

34. For 3700/4700 “BH” hydraulic drive assembly, go to Section 13, INSTRUCTIONS FOR ASSEMBLY OF A
TYPE “BH” HYDRAULIC DRIVE.
35. Read and understand all safety instructions and warnings before installing and operating pump.
3700/4700 “BH” Pumps (Positive Drive Mechanical Seal) (See Figure 15.1)
36. Install retaining ring (12) on drive shaft (32) to locate mechanical seal.
37. Carefully remove all burrs and sharp edges on shaft over which rotating element of seal will slide.
38. Apply a compatible lubricant to seal I.D. and to O.D. of drive shaft (32).
39. Slide rotating element of mechanical seal (11) onto drive shaft (32) before removing three or four clips that
are taped to rotating element. Push rotating element back against retaining ring (12), tighten setscrews in
seal, and remove clips that are taped to seal.
40. Slide faceplate end of drive shaft, with rotating element attached, into backplate (6A, B).
41. Install backplate end retaining ring (36A) on drive shaft (32). Install key (B) in keyway on drive shaft. Slide
drive gear (34) onto drive shaft. Install faceplate end retaining ring (36B) to secure drive gear.
42. Place appropriate number of gaskets (20) on backplate side of case (19A, B, C, D, E). Slide drive
gear (34), assembled with drive shaft (32), and backplate (6A, B) into case bore. Align backplate (6A, B)
on hollow dowel pins (J). Secure backplate (6A, B) to case (19A, B, C, D, E) using two washer head cap
screws (K) and eight hex head cap screws (L).
43. Lubricate o-ring on stationary seal face and seal chamber bore with a compatible lubricant. Slide stationary
seal face over keyway end of drive shaft (32) and down to seal chamber. Be sure lapped (polished) face is
toward rotating member of seal. Push stationary seal face into seal chamber.
44. Install antirotation pin (T) in locator ring (60).
45. Position locator ring (60) with antirotation pin (T) toward seal face. Align antirotation pin (T) with slot in
back of stationary seal face and push into counterbore of backplate (6A, B).
46. Install seal retainer (9). Secure seal retainer in place using two hex head cap screws (E).
47. Install drive key (A).
48. For 3700/4700 “BH” hydraulic drive assembly, go to Section 13, INSTRUCTIONS FOR ASSEMBLY OF A
TYPE “BH” HYDRAULIC DRIVE.
49. Ball bearing (2) and retaining ring (3) are not used in this configuration.
50. Read and understand all safety instructions and warnings before installing and operating pump.
3700/4700 “HB” and 3722 “SBFO” Pumps (Standard Mechanical Seal) (See Figure 14.2)
51. Place drive gear (34) into case bore. Install key (B) in keyway of drive shaft (32). Slide drive shaft into bore
of drive gear.
52. Place appropriate number of case gaskets (20) on backplate side of case (19A, B, C, D, E). Align
backplate (6A, B) on dowel pins (J). Secure backplate to case using two washer head cap screws (K) and
eight hex head cap screws (L).
53. Install retaining ring (12) on drive shaft (32).
54. Carefully remove all burrs and sharp edges from shaft over which rotating element of seal will slide.
55. Lubricate drive shaft and mechanical seal bore with a compatible lubricant. Install mechanical seal (11) on
drive shaft and position seal back against retaining ring (12). Care must be taken not to nick o-ring. Be
sure lapped (polished) faces of stationary seal face and rotating elements are together.
56. Install ball bearing (2) on drive shaft (32) and into backplate (6A, B). The bearings are prelubricated and do
not require lubrication at time of initial installation. A small amount of grease will be required during regular
maintenance. Tighten setscrews in ball bearings (2) to secure bearing on drive shaft (32). Install retaining
ring (3) into backplate (6A, B) to secure ball bearing (2) to backplate (6A, B).
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