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Generac — WARNING

A Generac service procedure — check it applies to your exact model before use.

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Before you start

  • Before attempting to service the pump, read this manual carefully. Also review all
  • If this pump is used to handle any hazardous materials that can cause injury or illness,
  • s by wearing approved protective clothing and use appropriate safety
  • Use lifting and moving equipment that is in good condition and that has adequate
  • that all work must be performed by qualified personnel.
  • when removing the impeller.
  • The shaft will not rotate. Tighten bearing housing jack screws until .010 to .020 in (.25 to .50 mm) increase in
  • Over-filling with oil can result in premature failure of bearings.
  • S
  • ous materials that can cause injury or illness,
  • IT IS RECOMMENDED THAT THE PRESSURE RELIEF VALVE ASSEMBLY BE

Procedure

  1. Disconnect the battery cables.
  2. Store the unit off the ground so no water will accumulate around the equipment.
  3. Protect unit from blowing sand and dirt.
  4. Stack no other items on top of pump/equipment.
  5. Protect unit from the entry of any animals.
  6. Periodically rotate shaft to lubricate bearings and protect bearings from brinelling.
  7. Protect unit with approved drying agents.
  8. Ensure all bare metal areas are coated with rust preventative.
  9. Inspect unit every four weeks and replace drying agents (Silica Gel) as required, or a minimum of every
  10. Keep an inspection record showing dates of inspection with any maintenance preformed and condition
  11. Before use, ensure that all rust protection has been removed. Also, remove any foreign material that
  12. Before use, remove all drying agents (Silica Gel).
  13. Pump not primed
  14. Suction line not filled
  15. Air pocket in suction line
  16. Suction inlet or foot valve
  17. System head higher than
  18. System head lower than pump
  19. Insufficient NPSH
  20. Parallel pump application is
  21. Suction pressure to vapor
  22. Suction lift too high
  23. Excess vapor in pumpage
  24. Specific gravity of pumpage
  25. Viscosity of pumpage different
  26. Operation at below rated
  27. Cavitation
  28. Electrolysis
  29. Impeller obstructed
  30. Wrong-rotation direction
  31. Low speed
  32. Air leak into suction line
  33. Air leak through mechanical
  34. Seal fluid contaminated, hot or
  35. Seal fluid system not vented
  36. High speed
  37. Mechanical seal insufficient
  38. Bearing housing excessively
  39. Low oil pressure (oil lube bear-
  40. Improper or poor lubrication
  41. Lubrication defective
  42. Dirt in lubrication/bearings
  43. Moisture in lubricant/bearing
  44. Lubricant excess
  45. Pipe strain
  46. Temperature growth
  47. Misalignment
  48. Coupling improperly installed
  49. Impeller installed backwards
  50. Wear rings worn
  51. Impeller damage
  52. Improper balance (after
  53. Bent shaft
  54. Excessive thrust
  55. Rotational element dragging
  56. Worn or incorrectly installed
  57. Mechanical seal not properly
  58. Shaft scored at seal
  59. Volute O-ring
  60. Foundation not rigid or settle
  61. Suction line collapsed
  62. Not enough liquid in casing
  63. Suction check valve contami-

Tools required

  • (237 Nm), maximum of 235 ft-lb (118 Nm). Do not allow the shaft
  • ent
  • ent
  • puller
  • puller
  • puller
  • gauge
  • gauge
  • gauge

Specs & torque values

  • 237
  • 118
  • 175
  • 235
  • of .025 to .035 in (.63 to .89 mm) between the impeller and the seal plate is
  • between the impeller and the rotating assembly with the rotating assembly sitting on the
  • is achieved.
  • can be determined by taking measurements of the gap between the pump casing and the bearing
  • is achieved at each corner of the bearing housing.
  • can be opened on the ES- series without removing the rotating assembly by loosening the
  • between the pump casing and the bearing
  • until the above
  • between the adjustment flange and the volute casing.
  • 41207

Source: manual:41207.pdf. Figures and steps are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.