Common Problems and Fixes

Learn the most common engine parts failures, what causes them, and the best repair solutions for pistons, cylinders, crankshafts, bearings, head gaskets and timing components 

Piston Failure

Excessive heat and lack of lubrication

Valve and Timing Failure

Excessive valve wear and/or stretched timing chain resulting in mistiming

Cylinder and Crankshaft Failures

Lack of lubrication resulting in excessive heat build up

Engine Tech

Common Engine Part Failures & How to Fix Them

Understanding common engine failures can help prevent costly damage and keep your machine running at peak performance. Below are common engine issues, their causes, and recommended fixes.

Piston Failure

Common Issues

  • Scored piston skirts
  • Burnt or melted piston crowns
  • Seized pistons

Causes

  • Overheating
  • Lean air/fuel mixture
  • Detonation or pre-ignition
  • Poor lubrication

Recommended Fix

  • Replace piston and inspect cylinder walls
  • Correct fuel mapping or carb settings
  • Ensure proper cooling and oil supply
  • Upgrade to forged pistons for high-performance applications

Crankshaft Bearing Failure

Common Issues

  • Knocking or rumbling noise
  • Excessive engine vibration
  • Metal shavings in oil

Causes

  • Oil starvation
  • Contaminated oil
  • High RPM stress

Recommended Fix

  • Replace crank bearings and inspect crank journals
  • Flush engine thoroughly
  • Maintain proper oil intervals and quality

Timing Chain / Valve Train Failure

Common Issues

  • Engine will not start
  • Rattling noise from engine
  • Severe internal engine damage

Causes

  • Wear over time
  • Improper valve clearance
  • Timing issues

Recommended Fix

  • Replace timing chain and/or tensioner
  • Replace damaged valves, springs, or camshaft
  • Adjust valve lash to manufacturer specifications
  • Verify proper timing chain or belt alignment

Head Gasket Failure

Common Issues

  • Engine overheating
  • White smoke from exhaust
  • Milky oil (coolant contamination)

Causes

  • Overheating
  • Warped cylinder head
  • Improper installation torque

Recommended Fix

  • Replace head gasket
  • Resurface cylinder head if necessary
  • Ensure proper torque sequence and cooling system function

Oil Pump Failure

Common Issues

  • Low oil pressure warning
  • Engine ticking or knocking
  • Accelerated engine wear

Causes

  • Debris in oil
  • Worn internal components
  • Lack of maintenance

Recommended Fix

  • Replace oil pump
  • Clean oil passages
  • Use high-quality oil and filters
Pro Tip: Routine maintenance such as oil changes, proper tuning, and regular inspections can prevent many major engine failures and extend engine life.