# Diesel Engine Pre-Shipment Inspection Checklist for Buyers

> Diesel engine pre-shipment inspection checklist: what the test report and video should show, from nameplate and oil pressure to leaks and packing.

- URL: https://www.marine-equipment-supply.com/blog/diesel-engine-genset-pre-shipment-inspection-checklist/
- Published: 2026-08-06
- Updated: 2026-08-27
- Author: MARS Engineering & Sales Team, Shanghai Mars Industrial Co., Ltd.

A proper pre-shipment inspection shows that the engine you are paying for is the right model, runs correctly and is packed to survive the trip. At a minimum, the test report and video should cover the nameplate and serial number, a cold or warm start, a stable run with oil pressure and coolant temperature readings, and a check for leaks, abnormal noise and smoke. They should also confirm the agreed accessory list and show the finished packing. For higher-value orders, an independent third-party inspector can witness the same checks on your behalf.

## Key takeaways
- The inspection should tie one specific serial number to one specific test. The nameplate or stamped number has to appear in the video and on the report.
- A run test should record oil pressure, coolant temperature and speed at idle and at higher speed, and compare them with the manufacturer's limits.
- Leaks, abnormal noise, excessive smoke and unstable speed are the main visible warning signs in a run video.
- The accessory list and packing photos matter as much as the run test, because missing parts and poor crating cause many post-delivery disputes.
- Wooden packaging made of solid wood generally has to comply with ISPM 15 (heat-treated or fumigated and marked). Plywood and other processed wood are generally exempt.

## What should an engine test report include?
A useful machinery test report is a single document for each engine that someone other than the tester can check. It should contain at least the following:

| Section | What it should show |
| --- | --- |
| Identification | Engine model, serial number, rating (kW and rpm), emission version, date of test |
| Pre-start checks | Oil and coolant filled to spec, fuel system bled, battery voltage |
| Run data | Speed, oil pressure, coolant temperature, run duration at each step |
| Observations | Leaks, noise, smoke, vibration, any adjustments made |
| Accessories | Checklist of items fitted or packed loose (alternator, starter, radiator, ECU, panel) |
| Sign-off | Tester name, and the photos and video file references |

For genset engines, add the governed speed (1,500 rpm for 50 Hz or 1,800 rpm for 60 Hz) and, where the engine is tested with an alternator, the load steps applied. Complete generator sets are commonly specified and tested against ISO 8528, so ask which parts of that standard the test follows.

## What should the inspection video show?
Videos are the easiest evidence to fake or misread, so ask for a continuous take where possible, without cuts between the identification shot and the running shot. A good video covers these steps:

1. **Nameplate and serial number.** A close-up that is readable on a phone screen, followed by a slow pan back to the whole engine so the viewer can see that the plate is on this engine.
2. **Start.** The engine starts from the key or button, and the viewer can hear the starter crank.
3. **Idle.** A stable idle with no hunting. The camera shows the oil pressure gauge or display and the tachometer.
4. **Speed increase.** The engine is taken up to rated or governed speed and back down, and responds cleanly.
5. **Walk-around while running.** Both sides, the front pulley and belts, the turbo, the exhaust outlet and the underside where oil or coolant would drip.
6. **Exhaust smoke.** Some smoke at start-up is normal, but continuous heavy black, blue or white smoke needs an explanation.
7. **Shutdown and post-run check.** The engine stops cleanly, and a final look shows no fresh leaks.

## How do I judge oil pressure, temperature, leaks and noise?
Correct values differ by engine model, so compare readings with the manufacturer's data sheet or workshop manual rather than a general rule.

- **Oil pressure.** It should rise quickly after start, stay steady at idle and increase with speed within the specified range. A pressure that drops as the engine warms up, or flickers, needs investigating.
- **Coolant temperature.** It should climb steadily toward normal operating temperature and settle there once the thermostat opens. On a short bench test the engine may not reach full temperature, so the report should state how long it ran.
- **Leaks.** Check the oil pan, rocker cover, front and rear crankshaft seals, turbo oil lines, injection pump, fuel lines and water pump. Wet spots after a short run are not normal on a new engine.
- **Noise.** Listen for knocking that changes with speed, a turbo whine that rises sharply, or rattles from the front of the engine. Uneven running or misfiring can point to injection or valve problems.
- **Blow-by.** On diesel engines a small amount of crankcase vapor is normal, but heavy, pulsing blow-by from the breather is a warning sign.

For electronically controlled engines such as the [Weichai WP13.530E40](/products/diesel-engines/weichai-wp13-530e40-truck-diesel-engine-390-kw-530-hp/), also ask for a screenshot or reading of active fault codes from the diagnostic tool. For gas engines such as the [Weichai WP6D132E301NG](/products/gas-engines/weichai-wp6d132e301ng-6-cylinder-natural-gas-engine-120-kw/), confirm what gas the test ran on. In our [gas-field power project](/projects/natural-gas-genset-engines-weichai-wp6/), the engines were factory-tested on gas before dispatch.

## Which accessories and packing details should be photographed?
Many delivery complaints are about parts that are missing or damaged, not about how the engine runs. Before the crate is closed, ask for:

- A photo of every loose item laid out next to a printed packing list: ECU, harness, radiator, control panel, filters, manuals and spare kits.
- Close-ups of vulnerable points that should be covered or protected: turbo inlet and outlet, exhaust flange, electrical connectors and the injection pump.
- Photos of the engine bolted down to the crate base, not just resting on it.
- The closed crate with shipping marks, engine serial number and gross weight visible.
- The ISPM 15 mark on solid-wood packaging, if solid wood is used.

## How should buyers use third-party inspection?
A third-party inspection company such as SGS, Bureau Veritas or Intertek, or an independent engineer, can attend the test and packing in person. This is most useful for first orders with a new supplier, for batch orders, and for engines going into critical service such as prime-power gensets or marine propulsion.

To get value from an inspector:

1. **Write the checklist yourself.** Base it on the sections above and send it to both the inspector and the supplier before the booking date.
2. **Define pass and fail criteria.** Examples: the serial numbers must match the pro-forma invoice, there must be no active leaks, and oil pressure must be within the manufacturer's specification at idle and rated speed.
3. **Book it against the production schedule.** Built-to-order engines typically take around 20 working days, so book the inspection for when the engines are finished but not yet crated.
4. **Ask for raw evidence.** Photos and videos should come with the inspector's report, not just a pass/fail certificate.
5. **Handle failures in writing.** Agree in advance what happens if a unit fails, for example rectification and re-test before the goods are released.

For batch orders, one approach is to have every engine run-tested with its own report, and to have the inspector witness a sample plus the packing. This is how our [genset assembler project](/projects/genset-assembler-cummins-6bt-6cta/) handled repeated batches of [6BT](/products/diesel-engines/cummins-type-6bt-diesel-engine-for-genset-and-marine-80-210-hp/) and [6CTA8.3](/products/diesel-engines/cummins-type-6cta8-3-diesel-engine-8-3-l-80-210-hp/) engines, each shipped with a serial-number list and test reports.

## What is a practical inspection checklist?
| Check | Evidence | Pass criterion |
| --- | --- | --- |
| Model and serial | Photo and video close-up | Matches order and invoice |
| Start and idle | Video | Starts cleanly, stable idle |
| Oil pressure | Gauge in video and report | Within the maker's specification |
| Coolant temperature | Gauge and report | Rises and stabilizes normally |
| Leaks | Walk-around video | No active oil, fuel or coolant leaks |
| Noise and smoke | Video with sound | No knocking, no persistent heavy smoke |
| Fault codes (electronic) | Diagnostic reading | No active codes |
| Accessories | Photo against packing list | All listed items present |
| Packing | Photos of fixed engine and closed crate | Secured, protected, marked |

MARS runs each engine through a machinery test with a written report and video before dispatch, and welcomes buyer-appointed inspectors. To arrange a witnessed test, get in touch through the [contact page](/contact/).

## Frequently asked questions
### Is a supplier's test video enough, or do I need third-party inspection?
For stock engines from an established supplier, a continuous test video with a matching serial number and a written report is often enough. For first orders, large batches or critical applications, a third-party inspector adds independent verification.

### How long should a pre-shipment run test last?
There is no single standard duration for a bare engine. Agree the duration and the speed steps in advance, and make sure the report records them. Genset packages tested under load usually follow the load steps the buyer specifies.

### What does a failed inspection usually lead to?
Normally the supplier rectifies the problem and re-tests the engine, with a new video or a re-inspection before shipment. Agree this procedure in writing before the inspection takes place.

### Should gas engines be tested differently from diesel engines?
The same identification, leak, noise and packing checks apply. In addition, confirm the fuel gas used in the test, the ignition system and the gas train, and any speed-governing settings for genset duty.

### What packing standard applies to wooden engine crates?
Solid-wood packaging in international trade generally has to meet ISPM 15, which means heat treatment or fumigation plus the official mark. Crates made of plywood or other processed wood are generally exempt, but check the destination country's rules.