Common Issues with Stackers and How to Resolve Them

Stackers are a key part of daily operations in warehouses, distribution centres and manufacturing environments. They allow teams to move and position pallets safely, especially in tight areas where larger machinery would struggle. However, like all regularly used equipment, stackers can develop mechanical or operational issues over time. These faults are often manageable if identified early, helping businesses avoid downtime, maintain safety and extend the lifespan of their equipment.

Below, we explore the most common stacker problems and the best ways to resolve them, combining practical guidance with clear explanations to support both operators and maintenance teams.

---

1. Lifting Problems

Lifting issues are among the most frequent faults seen with both manual and electric stackers. When a stacker struggles to lift or refuses to lift altogether, it can slow operations and create safety concerns. These faults are usually linked to the stacker’s hydraulic system.

Common causes of lifting problems:

• Low hydraulic oil levels

• Air trapped inside the hydraulic system

• Worn seals or hydraulic leaks

• Loads exceeding the stacker’s safe working capacity

To fix lifting issues, the first step is to inspect the hydraulic system. Topping up oil, checking the condition of seals and bleeding air from the system can often restore normal operation. It’s also important to make sure loads are always kept within the weight limit, as repeated overloading will quickly wear out the hydraulic components.

2. Mast or Fork Misalignment

A misaligned mast or uneven forks can make loads wobble or tilt, making lifting and moving far less stable. This problem may develop slowly through everyday use, or it can happen suddenly if the stacker experiences an impact—such as hitting racking or striking an uneven surface.

Signs your mast or forks may be misaligned:

• Loads tilt or lean when lifted

• Forks appear uneven when lowered

• The mast moves roughly or feels loose

• The machine struggles to raise loads smoothly

Correcting these issues often means inspecting mast rollers, bearings and fork condition. Bent forks need replacing rather than straightening, while damaged rollers should be swapped out to restore smooth tracking. More serious cases may require a professional engineer to realign the mast safely.

3. Battery and Power Issues (Electric Stackers)

Electric stackers rely heavily on battery performance, and power-related issues can quickly halt productivity. Frequent charging, heavy use and incorrect charging habits can all reduce battery lifespan.

Typical reasons for power problems include:

• Worn-out or sulphated batteries

• Loose or corroded terminals

• Faulty wiring

• Chargers not operating correctly

Many issues can be resolved by checking and cleaning connections, inspecting cables for damage and ensuring a correct charging routine (full charges rather than repeated partial ones). If the battery fails to hold power even after proper charging, a replacement battery is usually the most effective solution.

4. Steering and Manoeuvrability Problems

When a stacker becomes difficult to steer or feels unusually heavy during movement, the cause is often related to the wheels or steering components. These parts are constantly in motion, so general wear is expected over time.

Common steering-related faults:

• Worn or flat-spotted wheels

• Debris lodged in wheel housings

• Damaged steering arms or linkage

• Lack of lubrication on moving parts

Clearing debris, greasing joints and replacing worn castors or load wheels can restore smooth movement quickly. Since poor steering can lead to unsafe handling, it’s important to address these issues as soon as they arise.

5. Hydraulic Leaks

Hydraulic leaks can start small, a drip overnight or a small pool near the base, but they almost always get worse if ignored. Leaks reduce the machine’s lifting power and can indicate failing parts.

Areas where leaks commonly occur:

• Around seals

• Along hydraulic hoses

• At fittings and joints

• From an overfilled hydraulic reservoir

Repairing a leak usually involves replacing the damaged part, whether that’s a hose, seal or connector. After repairs, the system should be refilled correctly and any trapped air removed to restore full lifting capability.

6. Brake Malfunctions

Reliable brakes are essential for safe operation, especially when working on slopes or in confined spaces. When brakes fail to engage, stick or provide inconsistent stopping power, the machine becomes unsafe.

Typical causes of brake issues:

• Worn brake pads or shoes

• Dirt and debris around brake components

• Incorrect cable tension

• Lack of lubrication

Most braking issues can be solved by cleaning components, adjusting cables and replacing worn brake pads. Regular inspections help prevent these issues becoming dangerous.

---

Key Points at a Glance

• Stackers develop issues mainly due to wear, incorrect use or missed maintenance.

• Hydraulics, forks, batteries, wheels and brakes are the most common areas affected.

• Early diagnosis prevents costly repairs and avoids unnecessary downtime.

• Regular servicing is the best way to keep stackers safe, reliable and efficient.

• Nationwide Handling provides expert servicing, repairs and parts for all major stacker models.

The Importance of Preventative Maintenance

While faults are inevitable over time, most stacker issues can be reduced, or prevented entirely, through consistent servicing. Routine checks help spot worn components early, prevent sudden breakdowns and keep performance strong. This not only enhances safety but also ensures your team can work efficiently without unexpected equipment interruptions.

Nationwide Handling offers comprehensive support for manual and electric stackers, from scheduled maintenance to repairs and replacement parts. Whatever the issue, our experienced engineers are here to help keep your workplace moving smoothly.

Stackers are dependable tools, but like all equipment, they benefit from proper care and attention. Recognising the early signs of common faults and understanding how to address them will help protect your investment and maintain a safe working environment.

With support from Nationwide Handling, you can keep your stackers performing at their best and avoid costly downtime.