Auxiliary Engine tends to hunt

Q) An aux. Engine tends to hunt to such an extent that the engine speed variation prohibits the connection of the machine to the switchboard.
a) Possible causes of hunting b)& how to rectify

Ans:)

Possible Causes Rectification

Leakage or Breakage of Tighten or Replace
Fuel High Pressure Piping


Defective function of nozzle Leaky Nozzle - Clean or Replace
Uneven injection pressure through
nozzle - Adjust
Damaged Spring of Nozzle Holder - Replace

Defective function of injection pump Infiltration of air inside pump - Bleed air
Periodical hitch of plunger - Clean
or Recondition

Damage to Plunger Spring Replace

Wear to hitch of Tappet Roller Replace or Recondition

Improper positioning of Rack Adjust

Defective function of Delivery Valve
a)Damage to delivery valve spring Replace
b)Damage or Leakage of Delivery Valve Replace or Clean
c)Hitch of Delivery Valve Recondition or Replace


Defective Function of booster pump Recondition

Clogging due to dirty fuel filter Clean

Defective tachometer cable Replace


Governor malfunction
Dirty oil(sludge) in governor Drain Oil, clean governor and refill

Lost motion in engine linkage
or fuel pumps Repair governor; linkages and/or pumps

Spring on yield linkage to fuel
racks too weak Return governor to Factory for Repair

Power Piston is sticking Check for side play or bending of
output shaft

Faulty Linkages Check yield links, shutdown arrgts. etc.

Load Limit Shaft bent Replace

Governor Worn Return governor

Compensation Adjustment incorrect Adjust the needle valve &
Compensation adjusting pointer