Table of Contents
Reviewed and updated by ICD - Week 30/2026
A hand pallet truck that will not lift is the most common fault in a warehouse, and it almost always comes down to the hydraulic system losing pressure or a valve leaking. In most cases you can diagnose the cause and fix it yourself in 5 to 15 minutes without removing the pump. This guide walks through the five symptoms, the likely cause behind each, and the exact step-by-step fix for every one.
Quick diagnosis: 5 symptoms and their causes
| Symptom | Most likely cause | Difficulty |
|---|---|---|
| Pumping does nothing, forks stay down | Low hydraulic oil or a stuck piston | Easy DIY |
| Lifts but then sinks on its own | Worn or loose lowering valve | Easy DIY |
| Pump is stiff and rises slowly | Thick or insufficient hydraulic oil | Easy DIY |
| Pump is light but forks will not rise | Dirty or worn one-way (check) valve | Moderate |
| Oil leaking from the body | Failed piston seal | Needs a technician |
5 detailed fixes, one per cause
1. Check and top up the hydraulic oil (5 minutes)
Low oil is the single most common reason a hand pallet truck will not lift. Top it up before you do anything else.
| Step | What to do |
|---|---|
| 1 | Park the truck on a flat surface and lower the forks fully. |
| 2 | Find the oil fill plug, usually a round 20-25 mm bolt under the body. |
| 3 | Remove the plug and check the level with a dipstick; the minimum is two-thirds of the reservoir. |
| 4 | Top up with ISO VG 46 (or AW 46) hydraulic oil until full. |
| 5 | Pump 5-10 times; the forks should rise smoothly and hold position. |
2. Tighten the lowering valve (3 minutes)
If the forks lift but slowly sink, the lowering (release) valve is open or worn. It sits under the body near the pump handle and is usually a hand knob or a 13 mm nut.
| Step | What to do |
|---|---|
| 1 | Turn the lowering valve clockwise to fully closed (no excessive force needed). |
| 2 | Raise a load and wait 2 minutes; the forks should hold their position. |
| 3 | If it still sinks, the valve is worn and needs replacing (an inexpensive part you can fit yourself). |
3. Clean the one-way (check) valve (10 minutes)
When the pump moves easily but builds no pressure, the one-way valve is dirty and no longer seals. Cleaning it restores lift.
| Step | What to do |
|---|---|
| 1 | Drain the oil into a clean tray and remove the fill plug. |
| 2 | Locate the one-way valve: a small steel ball and a spring inside the pump body. |
| 3 | Remove the ball and spring, soak them in diesel for 5 minutes, then wipe clean. |
| 4 | Refit in the correct orientation, refill with fresh oil, and test pump. |
4. Replace the piston seal (technician or experienced DIY)
If oil is leaking from the body, the piston seal has failed. Use a genuine Xilin seal. If you are not experienced at disassembling a hydraulic pump, call an ICD technician rather than risk further damage to the cylinder.
5. Replace the complete hydraulic pump (when repair fails)
When no repair restores lift, fit a complete Xilin pump assembly. Remove the four mounting bolts, disconnect the oil line, fit the new pump, refill the oil and bleed the air. ICD stocks genuine Xilin pumps and can deliver same day in Hanoi and Ho Chi Minh City.
Summary: fix it yourself or call a technician?
| Situation | Decision | Time |
|---|---|---|
| Low oil, loose valve | DIY fix | 5-15 minutes |
| Worn lowering valve, dirty check valve | DIY or technician | 10-30 minutes |
| Piston seal, oil leak | Call a technician | Workshop job |
| Pump completely failed | Replace pump or truck | Same-day part swap |
Related articles
| Xilin hand pallet trucks and forklifts | ICD Vietnam packaging and material handling |
Frequently asked questions
1. Why does my hand pallet truck only lift after 30 pumps?
This is usually low hydraulic oil or a slightly worn one-way valve. Top up the oil first; if that does not help, clean the one-way valve.
2. What hydraulic oil does a hand pallet truck use?
ISO VG 46 or AW 46 hydraulic oil, available from forklift parts suppliers or ICD. Do not use motorcycle engine oil, as the viscosity is wrong for the pump.
3. Why does the truck lift but then slowly sink?
The lowering valve is open or worn. Close it fully clockwise; if it still sinks under load, replace the lowering valve, which you can fit yourself.
4. The pump feels light but nothing lifts. What is wrong?
The one-way check valve is dirty and no longer seals, so the pump builds no pressure. Drain the oil, clean the steel ball and spring, refit and refill with fresh oil.
5. How long should a Xilin hydraulic pump last before overhaul?
A Xilin hydraulic pump typically lasts 3-5 years with correct maintenance (changing the oil every 6 months). Early failure is usually caused by dirty or insufficient oil.
Contact ICD: Xilin parts and forklift repair
ICD Viet Nam Industrial Production Company Limited - exclusive distributor of Xilin (Ningbo Ruyi) hand pallet trucks in Vietnam, with a 2-year manufacturer warranty.
Genuine parts in stock: lowering valves, piston seals, hydraulic pumps and wheels, held in Hanoi and Ho Chi Minh City.
North: Floor 3, Thang Long A1 Building, Bau Hamlet, Thien Loc Commune, Hanoi - 0983 797 186 / 090 345 9186 / 090 5859 186
South: 551/212 Le Van Khuong, Tan Thoi Hiep, District 12, Ho Chi Minh City - 098 6784 186
Email: sales@icdvietnam.com.vn · Zalo: Chat on Zalo now
