Hand Pallet Truck Oil Leak: Causes, Diagnosis and How to Fix It

Reviewed and updated by ICD - Week 43/2026

A hand pallet truck that leaks oil almost always leaks from the hydraulic pump unit: a worn or torn ram seal, a scored ram, a filler plug or release valve gasket that does not seal, and, less often, a cracked pump body. Wipe the pump unit clean, lift a load and watch where the oil seeps out; that tells you which part has failed. Seepage at the rod neck calls for a new seal kit and a check of the rod; seepage at the filler plug or release valve means tightening it or replacing the gasket; a cracked pump body means replacing the pump unit.

This guide gathers the common causes and fixes for forklift leaks from the real experience of the ICD Vietnam technical team, who give advice through the hotline 0983 797 186 / 090 345 9186 / 090 5859 186.

Having worked with warehouse equipment since 2011, I can say there is nothing more annoying than a patch of oil spreading across the warehouse floor right under a hand pallet truck. A leaking truck not only makes a mess and dirties goods; it is also a safety warning and a sign that the truck’s performance is falling. Fortunately, most of these cases can be fixed once you understand the cause.

QUICK SUMMARY

• Common problem: an oil leak is one of the most common faults on hand pallet trucks, usually caused by hydraulic seals that wear or tear after a period of use.
• Core causes: the guide analyzes what makes a hand pallet truck leak oil: failed ram seals, a worn ram, the wrong oil, a release valve and filler plug that do not seal, and a cracked pump body.
• Do-it-yourself fix: how to locate the leak from the oil traces and a 3-step procedure for replacing the seals at home.
• Practical experience: notes on choosing seals and hydraulic oil following the manufacturer’s guidance, and when to call a professional repair service.

1. Signs of a leak and why it should not be ignored

The clearest sign of this fault on a hydraulic hand pallet truck is oil traces spreading on the floor where the truck is parked or along its route. You will also notice the truck’s performance dropping: the pump feels lighter, the forks rise slowly, cannot hold height, or the truck will not lift at all.

Many people ignore it because the truck still “manages” to work. But in my experience this is a serious mistake. A leak is not only a safety hazard (slippery floors) that dirties the floor and the goods; it also shows the pump unit is being damaged, and left alone it can lead to much heavier and costlier failures.

2. Main causes of oil leaks on a hand pallet truck

To fix it properly we need to find the right “disease”. In my experience, most leaks come from the first three causes below; the last three are less common but easy to miss because technicians tend to think only of the seals.

Failed hydraulic seals (seal kit)

This is the most common cause. Hand pallet truck ram seals are rubber rings whose job is to seal and keep hydraulic oil from leaking out. After a long time in service they wear, harden or tear, leaving a gap for oil to pass. The usual sign is slow, steady seepage around the rod neck, worse when lifting heavy loads.

Worn or scored ram

The ram is the main piston rod of the hydraulic pump. If it is scratched by impact, pitted by rust in a damp warehouse or worn by dirt, it destroys the rubber seals very quickly and causes a continuous leak even if you fit new seals. That is why some trucks leak again soon after a seal change: once the rod is damaged it must be polished or replaced.

Using the wrong hydraulic oil

Oil that is too thin, dirty oil carrying contaminants, or engine oil used in place of hydraulic oil can all make seals swell or shrink abnormally, causing leaks and shortening seal life. For Xilin hand pallet trucks, the manufacturer’s manual recommends 46# anti-wear hydraulic oil.

Release valve that does not close fully

The valve ball or seat picks up deposits from old oil, so the release valve does not close fully. Oil can seep around the valve unit, but an internal leak is more common: the forks rise and then sink slowly. The fault typically shows up more with heavy loads.

Filler plug or air bleed screw not tightened

After an oil change or repair, the filler plug or bleed screw was not tightened enough, or its gasket has hardened. Oil seeps intermittently with the pump strokes, pooling at the back of the pump unit rather than around the rod neck.

Cracked pump body

A truck that has been dropped or hit hard can crack its pump body. A small crack is hard to see by eye, and oil seeps from a spot with no seal or thread. Seals cannot fix this; the whole pump unit must be replaced.

3. Oil seeps where the fault is: locating the leak in 10 minutes

Before taking anything apart, spend a few minutes locating the leak. The method is simple: wipe the whole pump unit clean with a dry rag, put a clean sheet of cardboard under the truck, lift a pallet within the rated load, pump a few times and leave it still. The oil will show up at the exact leak point before it spreads elsewhere.

4. A 3-step guide to fixing the leak yourself at home

If the cause is failed seals, you can replace them yourself to save cost. The steps below are a short version; the full step-by-step seal replacement is in our separate guide to hand pallet truck seals.

Step 1: Prepare tools and a new seal kit

• Tools: wrenches, screwdrivers, pliers, a clean pan for the old oil and lint-free rags.
• New seal kit: this is the most important part. You need the seal kit that matches your truck’s model. A complete kit usually has several different rings and dust seals.
• New hydraulic oil: for Xilin trucks, 46# anti-wear hydraulic oil.

Step 2: Remove the hydraulic pump unit and replace the old seals

• Drain the old oil: lower the forks to their lowest position, remove the pump unit and turn it upside down so all the old hydraulic oil runs into the pan.
• Remove the pump unit: take off the release chain, the handle and the pins and bolts that hold the hydraulic pump unit to the frame.
• Remove the ram and replace the seals: carefully pull the ram out of the cylinder and inspect its surface. Use a small screwdriver to lift out the old seals and fit new ones. Make sure each type of seal goes in the right way round and in the right place.

Step 3: Reassemble, refill with new oil and test

• Reassemble: put the pump unit back together in reverse order, remembering to thread the release chain.
• Refill with new oil: use the right hydraulic oil for hand pallet trucks and fill to the specified level.
• Bleed the air and test: following the Xilin manual, move the lever to the lower position and pump the handle a few times to push the air out. Then test lifting and lowering under load, mark the ram and leave it for a few minutes to make sure the truck no longer leaks or sinks.

5. When should you call a professional repairer?

You should turn to a professional hand pallet truck repair service in these cases:

• You have fitted new seals but the truck keeps leaking. This is a sign the ram is scored and needs specialist treatment.
• Oil appears where there is no seal or thread, suggesting a cracked pump body.
• You do not have the tools or are not confident in your technical ability.
• The truck has other complicated faults besides the leak.

Frequently asked questions

1. Why is my hand pallet truck leaking oil at the wheels?

Oil around the wheels is usually leaking from the hydraulic pump unit and running down. The root cause is still a failed ram seal, or a filler plug or release valve that does not seal. Wipe the pump unit clean and lift a load to see the first point of seepage.

2. How much does a hand pallet truck seal kit cost?

The price of a seal kit depends on the truck model and where the parts come from, and in general it is much cheaper than replacing the whole pump unit. For an accurate price, send the truck model and a photo of the old seals to the seller.

3. How often should I check the hydraulic oil on a hand pallet truck?

According to the Xilin hand pallet truck manual, check the hydraulic oil level every 3 months and top up with 46# oil if low. If you see oil on the floor or the forks sink, check right away; do not wait for the scheduled date.

4. Why will a hand pallet truck not lift?

Three common causes: low hydraulic oil (add the right oil), worn seals (replace the seal kit) and a release valve that does not seal (check and clean the valve). Also check that the lever on the handle is in the lift position and bleed the air. Contact ICD Vietnam if the truck is still under warranty.

5. What if an electric truck will not charge its battery?

Check the power fuse, whether the battery terminals are rusty and whether the charger still works. If the battery is worn (fully charged but lasting only a short time), replace it with the type the manufacturer specifies.

6. What special policies does ICD Vietnam have?

ICD Vietnam distributes Xilin (Ningbo Ruyi) forklifts in Vietnam with a 12-month warranty. Delivery terms and technical support are stated specifically when you place an order.

Contact us for advice on the right truck

References

• Specifications and pump features of the BF-III and DF-III: Ningbo Ruyi (Xilin), Hand Pallet Truck.
• Xilin hand pallet truck user manual (Ningbo Ruyi): 46# hydraulic oil, air bleeding, daily, monthly and 3-month check schedule.
• ISO 3691-5:2014 Industrial trucks, Safety requirements and verification, Part 5: Pedestrian-propelled trucks: ISO.