Crank Walk

What is a "Crankwalk" or a 'walking' crankshaft? (Is it a crank with greasy hairy legs on crutches?)

A 'crankwalk' or 'walking' crankshaft, occurs when an engine has thrust bearing failure or "blown thrust". It is a common problem with Mitsubishi 2G 4G63 2.0 DOHC (Dual Over head Cam) engines, and we have the solution.

This condition occurs when the the crank suffers excessive movement (crankshaft end play) and causes the crank angle sensor reluctor plate to come into contact with the sensor.

Symptoms associated with the crankwalk:

  • Clutch sensitivity, strange disengage and engage points.
  • Ticking or strange noise from the pulley side of the engine when clutch is depressed.
  • Crank Angle Sensor errors ( check engine light )
  • Difficulty shifting
  • RPMS decreasing significantly when clutch pedal is depressed.
  • Clutch does not return or "sticks" to the floor after being depressed

When this happens the engine will stop running, or you will notice hard shifting, or low clutch pedal. You may also hear a slight ticking noise. There are several theories about crankwalk, however there is no 'rock hard' evidence that officially points out this problem. The movement can place excessive or uneven horizontal loads on the thrust bearings, causing premature failures or crank angle sensor failure. Mitsubishi has no recall or TSB regarding this problem.

It appears that Mitsubishi built many 2G engines that have this ailment, 1G owners ( 1990 - 1994) do not generally need to worry, as there aren't as many problems with cranks in those cars. But its possible to get crankwalk in any car. Mazda Miatas and Volga 2.1L engines are a couple of the few other cars known to have issues like this from the factory.

Do I have crankwalk?

You can diagnose whether or not your car has crankwalk by one of the easiest ways, install a dial indicator on the block place the finger of the indicator on the front pulley, carefully move the crank back and forth measure the amount of thrust, service limit is .011 or .26mm

What should I do to check or prevent crankwalk?

  • We recommend using a oil filter from a 1g at all times.. A larger oil filter and higher micron will provide for better filtration.
  • Pay attention to what your car is doing, keep an eye on your oil pressure, and make sure you perform proper maintenance at the scheduled times.
  • Keep an open mind about it. Crankwalk isn't something you can control, people get it stock or modified. There is no bearing on whether mods cause it or not. One option is building a 6 bolt and swapping it in.

In some advanced cases, the car will die when making a left hand turn or will be difficult to start.

Here are a few things to consider:

  • hardness of the crank
  • depth of hardness
  • method used to harden the crankshaft
  • bearing surface contact width
  • type of material bearing is made of
  • surface finish of the bearing and crankshaft
  • heat VS load and lubrication