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Can a 4 Cylinder Car Jump Start an 8 Cylinder Car?

by Ned Millis

The battery in your 8-cylinder Cadillac is dead. A motoring Good Samaritan rolls up and offers you a jump start with his 4-cylinder Japanese import. What are the chances that the 4-cylinder car can start the Cadillac with 8-cylinders?


Jump starting is not about cylinders; it is about power--power expressed in terms of voltage and the amount necessary to crank the engine of a disabled car.

Voltage and Power

Voltage power cranks engines

A battery stores power as the engine runs and sends a trickle charge to the battery. The power to start a car is delivered by the stored power. If the 4-cylinder car battery is good, it will work.

Safe Jump Start

The jumper cables must be placed correctly for a safe jump start with both car engines off and emergency brakes set. Connect the red/+ cable to the red terminal of the dead battery. Connect the other end of that cable to the red terminal of the good battery. Connect one end of the black/- cable to the good battery. Connect the other end of this cable to a piece of unpainted metal in the engine compartment of the car with the dead battery. Do not connect it to the black battery terminal. Start the car with the good battery and rev the engine. Attempt to start the car with the dead battery. If it starts, remove the cables in the reverse order they were placed.

What Starts the Dead Engine?

Once the jumper cables are correctly in place, the 8-cylinder car is started using the voltage supplied by the engine of the 4-cylinder car. Once the 8-cylinder car is running smoothly and jumper cables are removed drive the car with the dead battery to recharge it. You may want to take it to a place where battery service is offered and have it checked.

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