Description
A highly-illustrated (over 400 illustrations and photos) failure analysis guide for automotive and off-road vehicle parts. Lots of pictures and descriptions of common machine parts failures. Main topics include: Pistons, Rings, Cylinder Liners, Gaskets, Journal Bearings, Valve Gear Train, Turbochargers, Gears, Shafts, Axles, Spindles, Universal Joints, Hydrostatic Transmissions, Anti-Friction Bearings, Belts, Chains, Tracks, and Tires.
Author: John Deere
Format: Paperback
Pages: 202
Excerpt: SCUFFING AND SCORING
"Scuffing and scoring (adhesive wear) is caused by too much heat. When two metal parts rub and the heat builds up to the welding point, a small deposit or "hot spot" of metal is pulled out and deposited on the cooler surface.
"Scuffing leaves discolored areas on the surface of rings, pistons and cylinder walls.
"Scuffing starts as tiny surface disturbances. If they are not removed, scuffing spreads and becomes noticeable and more severe. It is then called scoring. Any engine condition which heats rubbing parts to the welding point, or which prevents the transfer of heat from these surfaces, influences scuffing.
"The following are possible causes of scuffing and scoring:
* Improper warm-up
* Lubricating system not functioning
* Cooling system plugged
* Combustion knock and preignition
* Lugging or overloading
* Misaligned connecting rod
"Occasionally an unusual wear pattern results from a misaligned connecting rod. Contact with cylinder wall shows on the bottom of the skirt at left, and at the ring lands on the right (arrows). There is also a diagonal wear pattern extending across the skirt of the piston. This uneven wear is due to a bent or twisted connecting rod or shaft. When connecting rods are misaligned, rings do not have proper contact with cylinder wall, pistons wear rapidly and unevenly, oil consumption is excessive and the engine is prone to scuff or score. Always check rod alignment.
Table Of Contents:
PISTONS, RINGS, CYLINDER LINERS AND GASKETS
Introduction
Identifying Piston Failures in Gasoline Engines
Detonation
Preignition
Scuffing and Scoring
Corrosive Wear
Physical Damage to Pistons
Identifying Piston Failures in Diesel Engines Cracking
Piston Breakage
Wear
Scuffing and Seizure
Erosion
Identifying Piston Ring Failures
Wear
Chipping
Scuffing and Scoring
Breakage
Sticking
Identifying Cylinder Liner Failures
Cracking
Chemical Attack
Cavitation
Wear
Scratching
Blown Head Gasket
JOURNAL BEARINGS
Introduction
Journal Bearings
Dirt
Lack of Lubrication
Improper Assembly
Misalignment
Overloading
Corrosion
Electric current
VALVE GEAR TRAIN
Introduction
Identifying Valve Failures
Distortion of Valve Seat
Deposits on Valve
Identifying Valve Failures
Too Little Tappet Clearance
Burned Valve
Erosion of Valves
Heat Fatigue
Pitting Breaks
Wear
Identifying Rocker Arm Failures
Identifying Push Rod Failures
Bent Push Rod
Identifying Valve Tappet Failures
TURBOCHARGERS
Introduction
Wheels and Impellers
Foreign Material
Sludge Build Up
Contact Damage
Abrasion-Erosion
Shafts
Oil Starvation
Contaminated Oil
Journal Bearings
Oil Starvation
Contaminated Oil
Unbalanced Rotating Assembly
Thrust Bearings
Oil Starvation
Contaminated Oil Housings
GEARS
Introduction
Gear Terminology
General Category of Failures
Wear Pitting, Spalling, and Case Crushing
Fatigue Impact
Rippling, Ridging, and Cold Flow
Combined Effects
Ring Gear Teeth
Ring Gear and Drive Pinion
Drive Pinions
Differential Side Gears and Pinions
Differential
Spider Arms and Side Pinions
Rear Axle
Differential Side Gears
Transmission Helical Gear
Transmission Splined Mainshaft
Transmission Countershaft
Transmission Mainshaft Second Speed Gear
Transmission Mainshaft Overdrive Gear
Transmission Countershaft Gear
Bumps, Burrs and Swells on Operating Transmission
Gear Teeth
Appearance of Failure
SHAFTS, AXLES, SPINDLES, AND UNIVERSAL JOINTS
Introduction
General Category of Failures
Overload Failure
Fatigue Failure
Torsional Fatigue
Severe Service Frettage and Scoring
Combined Fatigue Failures
Impact Failures
Improper Use
Specific Category of Failures
Crankshaft
Pump Shafts
Transmission Shafts
Spindles
Universal Joints
Lack of Lubrication
End Galling
Brinelling
Slip Spline Galling
Fatigue
Broken Journal
HYDROSTATIC TRANSMISSIONS
Introduction
Heavy Duty Hydrostatic Systems
Thrust Plate or Fixed Swashplates
Smearing or Galling
Scoring
Piston/Slipper Assembly
Scoring
Damaged Slipper
Rolled
Contaminated Slipper
Smearing or Galling
Discoloration
Piston Filler Separation
Slipper Separation
Slipper Retainer Discoloration
Scoring
Low System Charge Pressure
Ball Guides
Scoring
Worn Cylinder Block
Pulled Bushing
Fracture
Bearing Plates
Smearing-Outer Edge
Erosion
Grooved
Total Smearing
Discoloration and Smearing
Discoloration
Cavitation
Bi-Metal Bearing Plates
Total Smearing
Cavitation
Metal Separation
Valve Plate Contamination
Smearing
Grooving
Shaft Seal
Grooving
Scoring
Fracture
Charge Pump Assembly
Fractured Input Flange
Displacement Control Valve
Broken Spring
Broken Control Shaft
Servo Sleeve and Piston
Fracture
Scoring
Shafts
Worn Spline
Fractured Input Taper
Worn Spline
Light Duty Hydrostatic Systems
Stuck Piston
Valve Plate/Charge Pump Housing
ANTI-FRICTION BEARINGS
Introduction
Anti-Friction Bearings
Contamination
Improper Lubrication
Improper Installation
Careless Handling
Misalignment
Severe Service
Vibration
Electric Current
BELTS AND CHAINS
Introduction
V-Belts
Cracking
Rupture
Tear
Burn
Gouges
Wear
Internal Cord Failure
Cuts
Peeling, Fraying, Chewing
Banded V-Belts
V-Belts
Ridging Outside of Sheave Groove
Bottoms of Belts Cracking
Top of Band Frayed, or Damaged Band
Separating From Belts
Holes or Blisters in Tie Band
Special V-Belts
Frayed Edges
Narrow Wear in One Section
Drive Belt Disintegration
Drive Belt with Sheared Cogs
Flat Belts
Flat Belt Tears
Flat Belt Burn
Chains
Wear of Chains and Chain Parts
Fracture of Chains and Chain Parts
Corrosion of Chains and Chain Parts
TRACKS AND TIRES
Tracks
Links
Pins and Bushings
Sprockets
Rollers
Special Tracks
Cable and Edge Damage
Obstruction and Impact Damage
Face Damage
Lug Damage
Track Tension Damage
Tires
Fabric Breaks
Rubber Checks
Wear
Tread Wiping
Tread and Sidewall Cuts
MISCELLANEOUS FAILURES
Introduction
Pump Rotors
Pump Impellers
Disk Blades
Spark Plugs
Oil Test Kits
0-Rings
Intercooler Brace
Fasteners
Failures During Assembly
Galling
Bolt Yield and Tensile Failure
Nut/Cap Screw Thread Failure
Nut Dilation
Galling
Failures During Use or After Assembly
Fatigue Failure
Loss of Cap Screw Torque After Assembly
