Experiencing a forklift engine shutting off as soon as you shift into gear can be incredibly frustrating and disrupt operations. This issue, where the engine starts fine but dies when engaging forward or reverse, is a common problem faced by forklift operators and mechanics alike. Let’s delve into the potential causes behind this issue and explore troubleshooting steps to get your forklift back in action.
One user, Jerry, reported this exact problem with their Clark C30CL forklift. Initially suspecting fuses and relays, Jerry discovered the root cause was a loose connection in the dashboard. This highlights a critical, often overlooked area when diagnosing such problems.
Dashboard Connection Issues
As Jerry from Florida discovered, a faulty dashboard connection can indeed be the culprit. The dashboard in many forklifts, including Clark models, houses crucial control circuits. A loose or broken connection at the back of the dashboard can interrupt the electrical signals necessary for the engine to remain running when a load is applied by engaging the gear.
Troubleshooting Dashboard Issues:
- Access the Dashboard: Carefully locate and access the back of the forklift’s dashboard. This might involve removing a panel or cover, depending on the model.
- Inspect Connections: Visually inspect all wiring and connectors at the back of the dashboard. Look for any loose wires, corroded terminals, or damaged connectors.
- Check the Main Connector: Pay particular attention to the main connector block that plugs into the back of the dashboard. As Jerry mentioned, the screw holding this connector can loosen, or the plastic housing can break, leading to intermittent or lost connections.
- Secure Connections: If you find loose connections, gently but firmly re-seat them. If a screw is loose, tighten it carefully. If you notice any broken plastic components, they may need to be replaced.
- Test: After securing the connections, start the forklift and attempt to put it in gear to see if the issue is resolved.
Other Potential Causes
While the dashboard connection is a significant point to investigate, especially given the feedback from other users in the original forum, other factors can also cause a forklift engine to shut off when put in gear. These include:
- Faulty Seat Switch or Safety Interlocks: Forklifts are equipped with safety switches, often in the seat, that are designed to shut off the engine if the operator is not correctly positioned. A malfunctioning seat switch or other safety interlock could incorrectly sense that the operator is not present when the gear is engaged, causing the engine to die.
- Low Fuel Pressure or Fuel Supply Issues: Insufficient fuel supply can starve the engine when it’s placed under load. Check the fuel level, fuel filter (for blockages), and fuel pump for proper operation.
- Ignition System Problems: Issues within the ignition system, such as a failing ignition coil or distributor (in older models), could prevent the engine from maintaining combustion when the gear is engaged and load is applied.
- Transmission or Hydraulic Issues: Although less likely to directly cause the engine to shut off, severe problems in the transmission or hydraulic system that create excessive drag or load on the engine might contribute to stalling, especially if coupled with a marginal electrical or fuel supply issue.
- Engine Control Unit (ECU) or Sensor Malfunctions: In more modern forklifts, sensor malfunctions or ECU problems can lead to incorrect engine management when gear engagement signals are received. Diagnostic tools might be needed to read error codes in these cases.
Conclusion
When your forklift Engine Shuts Off When Put In Gear, systematically troubleshooting is key. Starting with the dashboard connections, as highlighted by the original forum discussion, is a practical first step, especially for Clark C30CL models. However, if the dashboard checks out, it’s essential to broaden your investigation to include safety switches, fuel supply, ignition components, and potentially more complex electronic controls. By methodically checking these areas, you’ll increase your chances of pinpointing the root cause and getting your forklift running smoothly again.
