When You Press the Raise Button, Does the Lift Motor Run at All, Run Briefly Then Stop, or Remain Completely Silent?

This is the single most important first question any technician (or shop owner) should ask when a two-post or four-post lift refuses to go up. The behavior of the motor in the first 3–5 seconds tells you which system has failed: electrical, hydraulic overload, or motor itself.

Scenario 1: Completely Silent – No Sound At All

If you hear absolutely nothing — no hum, no click, no relay sound — the problem is almost always upstream of the motor.

Most common causes in order:

1. No power reaching the control box– Blown shop fuse or tripped breaker (check the dedicated 30–50 A breaker).– Emergency stop button pushed in or faulty.– Broken or loose wire in the 220 V / 230 V single-phase feed (very common on older shops).

2. Failed up-button or pendantPress the button and use a multimeter to check for 220 V (or 24 V control voltage on some brands) leaving the button. A $12 pendant can save a $600 service call.

3. Burned or stuck power relay/contactorYou will usually hear a faint “click” from the control box when the button is pressed. If you hear the click but the motor stays silent, the main contactor is pitted or welded open. Replacement contactors cost $40–$90.

4. Door limit switch or safety switch openMany lifts will not raise if the carriage safety latch switch believes a latch is still engaged. Clean or bypass for testing only.

Quick test: Jump the two large terminals on the contactor with an insulated screwdriver (be extremely careful). If the motor runs, the problem is the coil circuit or button — not the motor.

Scenario 2: Motor Hums or Runs 1–3 Seconds Then Stops

This is classic overload or single-phasing.

1. Hydraulic overload / relief valve screaming or bypassingThe pump tries to build pressure but the relief valve is set too low or the cylinder is mechanically jammed (worn slide blocks, bent arm, vehicle too far forward). The motor pulls massive current and the internal thermal overload trips.

2. Run capacitor failed (single-phase motors only)A bad start/run capacitor causes the motor to draw 3–5× normal current. You’ll hear a loud 60-cycle hum, maybe a slight turn, then thermal cut-out. A $25 capacitor fixes 40 % of “motor runs then stops” complaints.

3. One phase dropped (3-phase lifts)If one of the three legs is lost (blown fuse in the shop panel), the motor will hum loudly but not turn. Check all three legs with a meter while pressing raise.

4. Seized or failing motor bearingsLess common, but if the motor has been wet or run low on oil (some older direct-drive pumps), the bearings lock and trip the overload.

Scenario 3: Motor Runs Continuously But Lift Doesn’t Move

Now we’re in hydraulic territory:

• Extremely low fluid (pump cavitates — you’ll hear a loud screaming/gravel sound).

• Broken motor-to-pump coupling (spider gear sheared).

• Pump itself worn out (vanes or gears no longer build pressure).

• Clogged suction filter/screen.

Why Eounice Car Lifts Rarely Show These Symptoms

Eounice designs its two-post and four-post lifts with several features that dramatically reduce “motor won’t run” calls:

• Oversized Italian or German hydraulic pumps with built-in adjustable relief valves that rarely stick.

• High-quality ABB or Schneider contactors and overload relays instead of cheap generics.

• Dual capacitor cans (one start + one run) on single-phase models — when one fails, the second often keeps the lift running until scheduled maintenance.

• Clear hydraulic sight glass and oversized reservoirs that make low-fluid problems obvious before damage occurs.

• Direct 2-year warranty on the power unit (most brands give only 1 year).

In real-world shops running Eounice lifts (models E4G 9,000–12,000 lb series and the low-ceiling J9X series), the most common “no raise” call is actually a $0.15 blown 5×20 mm control fuse — not a failed motor or pump.

Step-by-Step 5-Minute Diagnosis Flowchart

1. Verify 220–240 V at the main disconnect.

2. Press raise — listen for contactor click.

3. If click but no motor → check overload reset button (usually red on the motor).

4. If overload trips instantly → check run capacitor with a meter (should be ±10 % of rating).

5. If capacitor good → temporarily raise relief valve pressure 300–500 psi and try again (do this only if you know how).

6. If motor now runs and lift raises → slide blocks or mechanical binding was the root cause.

Real Shop Example

Last month a shop in Texas called because their 5-year-old lift “died overnight.” Motor was completely silent. Technician arrived, found the emergency stop button had been accidentally bumped by a rolling toolbox. 30-second fix — no parts.

Another shop in Florida had a lift that would run 2 seconds and stop every time. Diagnosis: run capacitor measured 3 µF instead of 45 µF. $28 part, 20-minute repair, back in service same day.

Prevention Checklist (Do This Monthly)

• Cycle the lift empty once to check for strange noises.

• Visually inspect hydraulic fluid level and color.

• Push the red overload reset button on the motor even if it doesn’t feel tripped.

• Wipe down the contactor contacts with a clean rag (prevents pitting).

When you need a lift that simply works day after day with minimal drama, more shops are switching to Eounice. Drop us an email at marketing@eounice.com and we’ll send you the latest 2025 catalog plus current promotions on 9K–15K two-post and four-post models with free shipping to commercial addresses in the lower 48.

Don’t let a $40 capacitor or a 15-cent fuse cost you thousands in lost bay time. The right lift and 5 minutes of monthly checks keep the bays full and the techs happy.