Satoh-S650G.com

Troubleshooting

Here you will find the factory troubleshooting information including symptom / possible cause and the recommended remedy for various issues related to your Satoh S650G Bison’s components and systems.

Format: Symptom & Possible Cause = Remedy

 

The Engine Lacks Power

Fuel Compression is Insufficient

  • Valve Clearance Improper = Adjust the Clearance
  • Valve Seat Leaky = Smooth Contacting Surface with Valve
  • Valve Stem Stuck = Replace Guide and Valve
  • Valve Spring Weak or Broken = Replace Valve Spring
  • Cylinder Head Gasket Leaking = Replace Gasket
  • Piston Ring Stuck or Broken = Replace Ring
  • Piston Ring or Cylinder Worn = Disassemble Engine  and Correct

Ignition Timing is Incorrect

  • Ignition Timing is Early or Late = Adjust Ignition Timing
  • Spark Plugs Faulty = Clean and Correct or Replace Spark Plugs
  • Distributor Points Faulty = Correct or Replace Parts

Fuel Level is Low

  • Carburetor Clogged = Disassemble and Clean Carburetor
  • Fuel Pipe Clogged = Clean Pipe
  • Fuel System Contains Air = Check Joints and Re-tighten
  • Fuel Pump in Poor Condition = Correct or Replace Pump
  • Fuel Filter Clogged = Replace Fuel Filter

Carburetor Draws Insufficient Amount of Air

  • Air Cleaner Clogged = Clean or Replace Air Cleaner

Engine Overheats

  • Cooling Water Insufficient = Add Coolant / Water
  • V-Belt Loose or Slippery = Adjust or Replace Belt
  • V-Belt Worn or Broken = Replace V-Belt
  • Thermostat Inoperative = Replace Thermostat
  • Water Pump Inoperative = Disassemble and Correct Pump or Replace
  • Radiator Clogged or Leaky = Clean and Correct or Replace Radiator
  • Ignition Timing Incorrect = Adjust Timing

 

Fuel Consumption is Excessive

Engine Oil Leaks

  • Oil Pan Drain Plug Loose = Re-tighten Plug
  • Oil Pan Set Bolts Loose = Re-tighten Bolts
  • Oil Pan seals faulty = Replace Oil Seals
  • Cylinder-head Gasket Broken = Replace Gasket
  • Oil Filter Set Bolts Loose = Re-tighten Filter Set Bolts
  • Rocker Arm Cover Packing Faulty = Replace Packing
  • Timing Chain Cover Packing Faulty = Replace Packing

Oil Comes Up into the Combustion Chamber

  • Piston Ring Damaged = Replace Piston Ring
  • Piston Ring End Gap Incorrect = Adjust End Gap
  • Piston Ring Worn or Stuck = Replace Ring
  • Piston and Cylinder Worn = Replace Piston or Cylinder Liner

Oil Comes Down From the Valve System

  • Valve Seat Worn = Replace Valve Seat
  • Valve Stem and Valve Guide Worn = Replace Valve and Valve Guide

 

Engine is Hard to Start

Engine has Starting Difficulty

  • Engine Oil too Thick = Replace Oil With Specified Brand
  • Battery Discharged = Charge Battery
  • Battery Capacity Low = Replace Battery
  • Battery Terminal Connection Faulty = Clean and Tighten Terminals. Replace Cables.
  • Starter Faulty = Disassemble Starter and Correct or Replace
  • Safety Switch Faulty = Adjust Clearance Between Cam and Switch, or Replace Switch

Ignition System is Defective

  • Distributor Points Faulty = Correct or Replace Points
  • Point Gap Incorrect = Adjust Point Gap to .018
  • Spark Plug Gap Incorrect = Adjust Spark Plug Gap
  • Spark Plug Cord Loose or Faulty = Re-tighten Cord Connection or Replace
  • Ignition Coil Faulty = Replace Coil
  • Primary Winding Connection Faulty = Check and Re-tighten Connection
  • Condenser Faulty = Replace Condenser

Engine

  • Valve Seized Up = Correct Valve or Replace
  • Piston, Piston Ring, or Cylinder Worn = Dissasemble and Correct
  • Cylinder Head Gasket Broken = Replace Gasket

Carburetor

  • Choke Valve Faulty = Correct or Replace Choke Mechanism
  • Idle Speed Circuit Faulty = Adjust
  • Carburetor Clogged or Too Dirty = Disassemble and Clean
  • Carburetor Mounting Bolts Loose = Re-tighten Bolts

 

Engine is Noisy

Piston

  • Piston-to-Cylinder Clearance Excessive Due to Worn Cylinder = Replace Piston and Cylinder Liner
  • Piston-to-Piston Pin Clearance Excessively Large = Replace Piston and Piston Ring
  • Piston Ring Broken = Replace Piston Ring
  • Piston Seized Up = Replace Piston

Crankshaft

  • Oil Clearance Excessively Large Due to Worn Main Bearing Metal = Replace Bearing Metal
  • Crankshaft Journal Worn = Machine Crankshaft or Replace
  • Main Bearing Metal Damaged = Replace Bearing Metal and Check Lubrication System

Connecting Rod

  • Oil Clearance Excessively Large Due to Worn Connecting Rod Bearing Metal = Replace Bearing Metal
  • Connecting Rod Bent = Correct or Replace Rod
  • Crank Pin Worn = Machine Crank Pin or Replace
  • Connecting Rod Bearing Metal Damaged = Replace Bearing Metal and Check Lubrication System

Miscellaneous

  • Valve Clearance Incorrect = Adjust Clearance Correctly
  • Crankshaft Thrust Washer Worn = Replace Washer
  • Engine Oil Level Low = Add Engine Oil or Disassemble and Correct Engine

 

Firing Irregularities

Ignition System

  • Ignition System Wiring Connection Loose = Check Connection and Correct
  • Spark Plug Faulty = Clean Spark Plug, or Correct, or Replace
  • Ignition Timing Incorrect = Adjust Timing

Air-Fuel Mixture

  • Air-Fuel Mixture Too Lean = Clean and Adjust Carburetor
  • Carburetor Clogged (or Dirty) = Clean and Adjust Carburetor
  • Ignition Timing Incorrect = Adjust Timing

Valves

  • Valve Clearance Incorrect = Adjust Valve Clearance
  • Valve Stuck = Disassemble Valve, and Correct, or Replace
  • Valve Spring Weak = Replace Spring
  • Valve Timing Incorrect = Adjust Valve Timing

Cylinder Head

  • Carbon Build-up in Combustion Chamber = Remove Carbon
  • Cylinder Head Gasket Leaky = Replace Gasket

 

Incorrect Idle Speed Adjustment

Carburetor

  • Idle Speed Adjustment Incorrect = Re-adjsut Idle Speed

Air Entering Fuel Line

  • Air Enters Carburetor Fuel Line = Re-tighten Carburetor Mounting Bolts
  • Intake Manifold Gasket Faulty = Replace Gasket

Valves

  • Valve Clearance Incorrect = Adjust Valve Clearance
  • Valve-to-Valve seat contact not perfect = Smooth Out Valve
  • Valve Stem-to-Valve Guide Clearance Excessively Large = Replace Valve and Valve Guide

Cylinder Head

  • Cylinder Head Gasket Leaky = Replace Gasket

 

Engine Runs Not Smoothly (When Accelerated)

Carburetor

  • Carburetor Acceleration Pump Circuit Clogged = Disassemble Carburetor and Correct
  • Air-Fuel Mixture Lean = Disassemble Carburetor and Correct

Ignition System

  • Spark Plug Faulty = Clean Spark Plug or Replace
  • High-Tension Wire Faulty = Replace Wire
  • Distributor Point Gap Adjustment Incorrect = Adjust Point Gap or Replace Points
  • Ignition Coil Faulty = Replace Ignition Coil

Engine

  • Valve Seized Up or Adjusted Incorrectly = Readjust or Replace
  • Compression Insufficient = Disassemble Engine and Adjust
  • Cylinder Head Gasket Leaky = Replace Gasket

 

Clutch Troubleshooting

Clutch Slips

  • No clutch free-play = adjust level nut of release level
  • Oil on clutch disc = replace
  • Wear in clutch disc = replace
  • Irregular height of release lever = re adjust with allowable limit 0.01in (0.4mm)
  • Incorrect release lever return = correct it
  • Weak pressure spring = replace

Clutch Drags

  • release lever height exceedingly shorter than specified = Readjust to 1.81in (46mm)
  • Disc vibrates considerably = replace if disc vibrates more than 0.03in (1mm)
  • Rust due to oil shortage in disc spline groove = clean rust and apply thin layer of grease

Shudder When Starting

  • Hardened Disc Surface = Grind it with sandpaper or replace
  • Exceeding Disc Shudder = Replace
  • Release lever height not uniform = adjust
  • Rust in disc spline groove = Correct and apply grease
  • Loosened or damaged tension spring = replace

Clutch Overheat

  • burnt release bearing = Replace
  • No clearance between release lever and release bearing = adjust release lever height

 

Steering Linkage Troubleshooting

Front Wheel Shimmy

  • Deformation of Front Wheel = Repair or Replace
  • Loose Front Wheel Screw = Re-tighten
  • Worn King Pin and Bushing = Change if Tolerance Serious
  • Play – Tie Rod or Drag Link = Re-tIghten Lock Nut
  • Play – Ball Socket Assembly = Change
  • Loose Nut and Bolts = Re-tighten

Hard Steering 

  1. Front Tires not Properly Inflated = Inflate Tires
  2. Damaged or Worn Out Bearing Within Steering Box = Change
  3. King Pin Bushing = Change
  4. Maladjustment of Toe-in = Adjust 0 ~ 0.236in (0 ~ 6mm)
  5. Damaged Kin Pin Thrust Bearing = Change

Pulls to one side:

  • Worm Center Pin or Bushing = Change
  • Loose Screw to Steering Box = Re-tighten
  • Maladjustment of Toe-in = Readjust

Excessive Play on Handle

  • Worn Worm Wheel and Worm Gear = Change
  • Worn Ball Socket Assembly = Change

 

Brake System Troubleshooting

Brakes Insufficient

  • Small Pedal Travel = Adjust with the Adjustment Rod
  • Worn Lining = Adjust with the Adjusting Rod, or Replace
  • Uneven Lining Contact = Grind with Sandpaper
  • Burnt Lining = Replace
  • Oil Attached Due to Oil Leak = Replace

Brakes Remain ON

  • Little Pedal Play = Adjust with the Adjusting Rod
  • Loose Brake Spring = Replace
  • Loose Return Spring = Replace
  • Cross Shaft and Holder Sticking = Disassemble, Correct, and Supply Oil

Strange Sound Heard

  • Foreign Matter in Drum = Clear Away
  • Damaged Lining = Replace
  • Loose Brake Housing Securing Bolt = Re-tighten
  • Damaged Return Spring = Replace

 

Hydraulic System Troubleshooting (Section A – Height Control Only)

With Control Lever in the Lifting Pistion, Implement Will Not Move Up

  • The Weight of the Lower Link is Heavy at its End (more than 1102.5 lb) = Reduce the Weight
  • Oil Pump Will Not Discharge Oil (Drive Shaft Broken) = Replace Pump, or Check for Causes
  • Relief Valve Set Pressure is Low = Replace Relief Valve Assembly, or Readjust it on a Bench Stand
  • Unload Valve Will Not Close = Make Sure the Unload Valve’s Slide is not Dusty nor Scratched. If Dusty, Wash Carefully. If Scratched, Give Lapping. If the Scratch is Negligible, Smooth it off with Oil Stone.

With Control Lever in the Neutral, Implement Will Show Hunching or Lowering from the Lifted Pistion

  • Clearance Between Spool Valve and Sleeve is too Large = Replace Spool Valve and Sleeve as an Unit Assembly
  • Steel Ball Seat is Scratched = Replace Ball Seat
  • Spool Valve Sleeve “O” Rings (two), Check Valve Plug “O” Rings (two), and Control Valve and Hydraulic Lift Case “O” Ring on the Cylinder Side Are Broken = Replace Damaged “O” Rings
  • Cylinder is Leaking in its Inside = Check Piston’s “O” Ring or Back Up Ring. If Damaged, Replace

Lifting Speed is Slow (Engine Speed 2800 rpm @ 1100lb @ 1.2sec)

  • Clearance Between Unload Valve and Valve Body Lap is too Large = Replace Valve Assembly or if Impossible, Replace Defective Parts Only
  • Relief Valve Seat is Scratched and Leaky = Replace Relief Valve Assembly
  • Pump’s Volumetric Efficiency is Low = Replace Pump
  • Suction Strainer is Clogged = Wash Strainer and Replace Oil
  • Implement is too Heavy = Reduce the Weight

With Control Lever in the Lowering Pistion, Implement Will Not Lower

  • Spool valve is Stuck = Make Sure that Sleeve and Spool Valve’s Lap are not Dusty. If Found Dusty, Thoroughly Clean. Check Valve’s Contacting Surface for Scratches
  • Return Spring is Broken = Replace It
  • Lock Valve is Closed = Disassemble and Clean it

Control Valve Lever Will Not Move Upward

  • Spool Valve is Stuck = Make Sure that Sleeve and Spool Valve’s Lap are not Dusty. If Found Dusty, Thoroughly Clean. Check Valve’s Contacting Surface for Scratches
  • Return Spring is Broken = Replace It

Oil Temperature is too High

  • Oil Pump is Seized Up = Replace Oil Pump (Check for Oil Contamination)
  • Oil Pump’s Volumetric Efficiency is Low = Replace Oil Pump
  • Clearance Between Unload Valve and Body’s Lap is too Large = Replace the Assembly. If Impossible, Replace Either of Unload Valve and Body, Whichever Worn
  • Relief Valve is Under Operation = Check for Control Valve Highest Position. Check for Stopper. Adjust.
  • Relief Valve Seat is Scratched, Causing Oil Leakage = Replace Relief Valve Assembly

Informal Noise

  • Pump is Seized Up = Replace Pump
  • Pump Suction is Insufficient = Check for Oil Quality. Check for Clogging of Suction Strainer
  • Excessive Suction of Air
  • Hydraulic Oil = Check of the Oil is as Specified

 

Hydraulic System Troubleshooting (Section B – Sub-Control Valve)

With Sub-Control Lever in the Lifting Pistion, Implement Will Not Move Upward

  • Implement’s Weight is too Heavy = Check for Weight
  • Oil Pump Will not Discharge Oil = Check for Drive System
  • Relief Valve Set Pressure is Low = Replace Assembly or Readjust on a Bench Stand

Lifting Speed is Slow

  • Relief Valve Seat Surface is Scratched = Replace Seat
  • Pump Volumetric Efficiency is Low = Replace Pump
  • Suction Strainer is Clogged = Replace Working Oil or Clean Inside of Hydraulic System
  • Hydraulic Oil = Replace it with specified Oil

With Sub-Control Lever in the Neutral, Implement With Load Will Lower

  • Body and Spool Working Parts are Worn = Replace Sub-Control Valve as an Unit. Check for Oil
  • Hydraulic Oil = Replace it with specified Oil
  • Inside of the Cylinder on the Implement Side is Leaky = Check for Cylinder or Replace
  • Piping Between Valve and Cylinder is Leaky = Replace Leaky Parts

Sub-Control Lever Will Not Automatically Return to Neutral

  • Return Spring is Broken = Replace Spring
  • Body and Spool Working Parts are Dusty = Disassemble and Wash Dirty Parts. If Found Scratched, Smooth it out with Oil Stone. Replace Oil