Can You Push Start An Automatic

Can You Push Start an Automatic? A Comprehensive Guide

The question, "Can you push start an automatic?" is a common one, often sparking debates among car enthusiasts and novices alike. The short answer is: generally, no, you can't push start an automatic transmission car. However, there are nuances to this seemingly simple answer, and this comprehensive guide will delve into the reasons why, the exceptions, and what to do if you find yourself in a situation where you need to get your automatic transmission car moving without the use of its starter motor.

Understanding Automatic Transmission Systems

Before diving into the specifics of push-starting, let's understand how automatic transmissions function. Unlike manual transmissions where the engine's power is directly transferred to the wheels via a clutch, automatic transmissions utilize a complex system of hydraulics, torque converters, and planetary gearsets. The torque converter acts as a fluid coupling, transferring power from the engine to the transmission. Crucially, this system needs the engine to be running to properly function.

The Role of the Torque Converter

The heart of the problem lies within the torque converter. When the engine is off, the torque converter is essentially locked, preventing the engine from being cranked by the force of the push. The engine needs to be spinning at a certain speed for the torque converter to engage and begin transferring power to the transmission. Pushing the car simply isn't going to generate enough force to spin the engine and overcome the torque converter's resistance.

The Importance of the Starter Motor

The starter motor is an electric motor specifically designed to rotate the engine crankshaft quickly enough to initiate combustion. It's the crucial component that overcomes the initial inertia of the engine and gets it running. Pushing the car attempts to replicate this function mechanically, but it lacks the necessary precision and power. The starter motor also supplies the essential power to the car's electronic systems, which are needed for the car to start and function correctly.

Why Push-Starting an Automatic is Usually Impossible

Several factors contribute to the impossibility of push-starting most automatic transmission vehicles:

• Torque Converter Lock-Up: As mentioned earlier, the torque converter's design prevents the engine from easily being spun by external force. The fluid coupling requires engine power to function, not the other way around.

• Engine Inertia: Modern engines are relatively large and heavy. Overcoming the inertia (resistance to change in motion) of the engine and all its components requires significant force – far more than a typical push can provide.

• Transmission System Complexity: Automatic transmissions involve many moving parts, controlled by sophisticated electronic systems. These systems need the engine to be running and supplying power to operate correctly. Trying to force the transmission into gear while pushing the car could potentially damage it.

• Lack of Engine Speed: Even if you could somehow rotate the engine sufficiently by pushing, it wouldn't reach the necessary RPM to start without the precisely controlled and powered start that the starter motor provides.

Exceptions and Special Circumstances

While push-starting an automatic is generally not feasible, there are a few highly specific exceptions:

• Extremely Steep Downhill: On a very steep incline, gravity may provide enough momentum to overcome the torque converter's resistance and initiate engine rotation. This is incredibly risky and highly improbable in most situations. Damage to the transmission is a significant risk.

• Very Small and Lightweight Vehicles: In extremely lightweight vehicles with small engines, a concerted push from multiple people on a flat surface might theoretically provide enough momentum to spin the engine. Again, this is highly improbable and should not be attempted.

• Vehicles with Manual Valvebody: Some older automatic transmissions have a manual valve body. This allows for manipulation of the transmission's shifting mechanism, potentially making it easier to overcome the resistance of the torque converter. However, this requires detailed knowledge of the transmission system, and attempting it without this knowledge is extremely dangerous.

What to Do If Your Automatic Car Won't Start

Instead of attempting a futile and potentially harmful push-start, follow these steps if your automatic car fails to start:

1. Check the Battery: This is the most common cause of a car not starting. Use a multimeter or have someone jump-start your car.

2. Inspect the Starter Motor: If the battery is fine, the starter motor might be faulty. This requires professional attention.

3. Examine the Electrical System: Issues with the car's electrical system can also prevent it from starting. A faulty alternator, for instance, can prevent the car from starting after it runs down the battery. A mechanic can diagnose and fix these problems.

4. Call for Roadside Assistance: Avoid attempting to push start your car. Instead, contact a roadside assistance service or towing company for safe and efficient transportation.

5. Consider a Jump Start: The easiest and safest option is a jump start from another vehicle. Ensure you follow safety procedures to avoid short circuits.

The Dangers of Attempting to Push Start an Automatic

Attempting to force your automatic transmission vehicle to start via pushing can lead to a number of serious consequences, including:

• Transmission Damage: The most likely outcome is damage to your transmission. Forcing the components beyond their designed operational parameters risks severe and costly repairs.

• Engine Damage: While less likely, you could also damage your engine, especially if the internal components aren't properly aligned before attempting to force the engine to crank.

• Personal Injury: Getting injured while attempting to push a vehicle can easily happen due to lack of coordination and momentum management.

Conclusion

To reiterate, push-starting an automatic transmission car is generally not recommended and often impossible. The complexities of the automatic transmission system, specifically the torque converter, make this endeavor both impractical and risky. It's far safer and more efficient to address the underlying issue preventing your car from starting through proper diagnostics and repairs. Always prioritize safety and call for professional assistance when your car refuses to start, rather than attempting any risky maneuvers. Remember, repairing the actual problem is always better (and cheaper) than attempting a push-start and potentially causing irreparable damage.