Q:

What causes a piston rod to break?

A:

Quick Answer

Thrown rods or piston rod breaks happen due to oil problems, over-revving the engine, faulty piston bearings or normal wear and tear. A thrown rod leads to an engine stopped cold in its tracks.

Know More

Full Answer

A thrown rod pierces the engine block or causes the piston valve and cylinder unit to jam. In either instance, the event is a costly engine rebuild or replacement.

Proper oil level or lubrication prevents friction and engine overheating. Overheating leads to rod failure due to metal on metal friction, warped valves or warped pistons. Carbon buildup also leads to rod failure due to overheating. This problem shows as dark or black-colored oil. Maintaining the proper oil level and using the proper grade of motor oil minimizes these types of rod breaks.

Over-revving the engine can lead to rod breaks. The revving causes rod failure due to a valve's spring failing or being sucked into the engine.

Faulty bearings cause too much play in a crankshaft and stresses the rod. Continued stress causes metal fatigue and eventual rod failure. Engine knock is the usual symptom. Knocking may also mean worn pistons or worn piston valves. In these instances, auto repair sites recommend replacing the piston valve, rod and crankshaft as a unit.

Good auto maintenance extends an auto's life. However, a vehicle's age or high mileage may lead to a rod failure.

Learn more about Engine

Related Questions

  • Q:

    What causes an engine knock?

    A:

    An engine knock results from one of several problems such as a loose connecting-rod bearing, bad fuel mixture, worn spark plugs or carbon build up inside the cylinder walls. A vehicle experiencing a knock should be quickly inspected to avoid any serious damage to the internal components of the engine.

    Full Answer >
    Filed Under:
  • Q:

    What are some causes of an engine coolant leak?

    A:

    Blown head gaskets and broken hoses can cause engine coolant leaks. A cracked engine head or block can also cause the leaks.

    Full Answer >
    Filed Under:
  • Q:

    What causes a tapping noise in the engine of a minivan?

    A:

    Tapping noises from the engine compartment of a minivan lasting more than a minute but dissipating once the engine is warm are normally from leaks in the exhaust manifold. A tapping noise that lasts just a few seconds on startup is usually due to malfunctioning valve lifters, according to Auto Repair Help.

    Full Answer >
    Filed Under:
  • Q:

    What causes engine backfire?

    A:

    Engine backfire is caused by an imbalance in the air-to-fuel ratio of the vehicle. Backfires occur in one of two places. A backfire in the intake manifold is caused by a ratio that is too lean (not enough fuel). A backfire out of the exhaust system is caused by a ratio that is too rich (too much fuel).

    Full Answer >
    Filed Under:

Explore