Engine seized

A seized engine is a situation where one or more pistons have become stuck inside a cylinder. This can happen if the engine is not used for a very long time, or if the engine overheated or ran without lubrication.

Table of Contents

• 1. Symptoms
  • 1.1 Engine Won't Start
• 2. Causes
  • 2.1 Overheating
  • 2.2 Lack of Coolant
  • 2.3 Lack of Lubrication

Symptoms

Engine Won't Start

If the battery and starter are in good, working order, the failure of the engine to start may be a result of seizing. When the key is turned, the starter motor turns the --link(carpedia,450)crankshaft. If the engine is seized, the crankshaft will not move.

There may be a single click from the engine when the key is turned. This means the starter is working, but cannot turn the crankshaft.

Causes

Overheating

As the engine runs, the friction created by the moving parts produces heat. The heat expands the metal parts of the engine. The engine must operate within a specific temperature range to avoid damage. If it exceeds this range, the parts can lock up or be otherwise damaged.

Methods of cooling the engine during operation are coolant and oil.

Lack of Coolant

A lack of coolant circulating through the engine will prevent the heat from dissipating. The coolant level may be low, in which case there isn't enough coolant to remove the engine heat properly. The circulation of the coolant may also be hindered by something such as a malfunctioning water pump or thermostat.

Lack of Lubrication

Oil is used to lubricate the engine parts as well as remove heat. If the engine is running on little or no oil, the parts are rubbing together with no reduction in friction. This will increase both the wear on the parts and the heat generated by their movement. An engine running with low oil can be damaged very quickly.