How to Operate a Mini Excavator: A 6-Step Pre-Start Checklist

Note: this checklist was accurate as of Q1 2025. Specifications and control layouts can change by production year, so verify oil type, track tension and control pattern against the operator's manual for your serial number.

Who Should Use This Checklist

If you're about to operate a mini excavator for the first time, or you're taking delivery of a compact machine for a job, this list is for you. It's the six-step sequence I run before any Sany machine leaves my yard: walk-around, undercarriage, fluids, grease points, warm-up, and full function test. On a compact unit, it takes 15–20 minutes.

I'm the quality and brand compliance manager at a construction equipment dealer. I review roughly 300 units a year — excavators from the mini class up to the Sany 335 excavator, plus scissor lifts and compact loaders. Since Q1 2024, I've kept a rejection log for every unit that didn't pass. Most of the red flags I write aren't engine problems. They're small things that become expensive when you ignore them.

Step 1: Walk Around Before You Climb In

Start a full machine length away, not in the cab. Look at the machine's stance first: a mini excavator that lists to one side usually has a soft track tensioner or a worn idler, not an engine problem. Then get close enough to touch everything.

• Inspect the bucket: teeth, side cutters, bucket edge, and the quick coupler if one is fitted.
• Check hydraulic cylinder rods for scoring, bends, or dampness around the seals.
• Look at hoses where they rub against the boom or chassis. A shiny spot on a hose is a future leak.
• Check under the machine for fresh oil drips before you start it, not after.
• On used units, clean the serial number plate with a wire wheel on a cordless drill (my service truck has an old DeWalt drill for this) and compare the number against the title or rental agreement.

On a compact machine, you can see most of this from ground level. On a 335-size Sany excavator, I bring a scissor lift and inspect the cab roof and counterweight from above. The principle is the same: if you can't see it, you can't sign it off.

Step 2: Check the Undercarriage and Track Tension

This is the part that surprises people. From the outside, it looks like I'm just staring at rubber tracks for a few minutes. What I'm actually doing is looking for damage that costs $50 to fix now and a couple of thousand dollars to fix later.

• Park on hard, level ground and lower the blade before you measure anything.
• Look for cuts, missing lugs, exposed cord, and embedded wire or rebar in the rubber tracks. A small cut grows fast once gravel gets inside.
• Check both track tensioners for oil or grease weeping, and inspect the grease fitting for damage.
• Measure track slack the way the operator's manual tells you to, not the way someone on the internet tells you. Different models use different measurement points.
• Look around the final drive area for thin, dark streaks of hydraulic oil.

If you're renting or buying a Sany 6 ton excavator, this step is still quick. But it is not optional. From my rejection log, most premature track failures aren't the tracks' fault — they're a tension problem that was visible days before.

Step 3: Open the Panels and Check Fluids Cold

Check fluids before starting, not after a full day. Cold levels are the only levels that mean anything. This is also where a machine's service history shows up.

• Engine oil: pull the dipstick, wipe it, reinsert, and read. It should sit between the marks.
• Hydraulic oil: check the sight glass or dipstick at cold level. Low hydraulic oil causes cavitation, and cavitation damages pumps far faster than normal use.
• Coolant: check the expansion tank while cold. Do not open the radiator cap when the machine is warm.
• If the machine has a fuel water separator, drain a little fuel into a clear container and look for water.
• Run a flashlight along hoses and fittings, looking for damp spots or chafing.

Oil analysis is useful, but it won't help you on delivery day. The visual check catches the problems that are already there.

Step 4: Grease the Pivot Points Before You Operate

Mini excavators have fewer grease points than large excavators — which is exactly why people skip them. Grease is cheap. Replacing a pin and bushings because the bucket linkage ran dry is not.

Find the points in the operator's manual. Expect fittings at the boom pivot, the arm, the bucket linkage, and the bucket pin area. As you pump grease, watch the old grease push out. If it contains dirt or water, wipe it off and keep pumping until clean grease appears.

This step also catches wear before it becomes a breakdown. If you pump grease into a joint and the pin visibly moves, or grease escapes from somewhere it shouldn't, you've found the problem before the operator does.

Step 5: Start, Warm Up, and Verify Controls

Get in, fasten the seat belt, and check the control lock. On most compact excavators, joystick functions stay disabled until the lock lever or armrest is in the correct position.

Start the engine at low idle. Do not go straight to full throttle. Hydraulic oil is thick when cold; if you slam functions at full throttle, you're asking the relief valves to absorb the shock. Run at idle until the RPM is stable, then use medium idle and cycle each function lightly for three to five minutes. In cold weather, extend the warm-up.

The control layout on a mini excavator is easy to remember: the left joystick controls the boom and the swing; the right joystick controls the arm, sometimes called the stick, and the bucket. The blade and travel functions are usually pedals, but some units let you switch travel to hand levers. Confirm the control pattern in the operator's manual before you move the machine, and test every joystick direction gently before you add any load.

If you're building a fleet training program, use ISO 20474 as the safety baseline and the Sany operator's manual as the machine-specific reference. The manual is the authority for exact warm-up times and control settings.

Step 6: Run a Full-Cycle Function Test

A start-up test is not the same as a full-cycle test. Move each hydraulic function through its complete stroke at least three times: boom up and down, arm in and out, bucket curl and dump, blade up and down, and swing both directions. Then travel forward and reverse for about 30 feet in an open area, and turn both ways.

Watch the tracks while you travel. Listen for skipping, and stop if you smell hot rubber or hydraulic oil. Then park the machine, wait two or three minutes, and look underneath again. This is the step almost everyone ignores. Leaks often appear only after a circuit has been pressurized and moving.

Honestly, I've signed off a machine and still walked back to check one hose clamp after the customer started loading it. The checklist keeps that doubt manageable.

Common Mistakes That Cost Money

1. Running a cold machine at full throttle. This is the fastest way to shorten hydraulic pump life. Warm the machine up before you work it hard.
2. Skipping the post-test leak check. A dry floor before the function test means nothing if a hose starts weeping after the test.
3. Trusting the previous operator's report. 'It was fine yesterday' is not a maintenance record. Run the same checklist every time.

People assume the expensive parts — engine, hydraulic pumps, final drives — fail first. Most of the failures I log start with hoses, pins, bushings, and rubber tracks, which is exactly what this checklist catches.

One more thing. I'm often asked why our rental rate for a Sany 6 ton excavator isn't the lowest quote in town. The answer isn't marketing. In four years of managing equipment deliveries, the units that get this 15-minute check cost less per operating hour than the machines that get rushed straight to work. That lower upfront price stops mattering when the machine sits on day two.