OceanSphere
Engines
⚓ Working on this equipment?
Ask the AI troubleshooter, log your hours on board and turn them into invoice-ready service reports — for this exact model.
Start free — 14 days →
No credit card required
🔧 65 verified suppliers & service companies for Wärtsilä in the Maritime Network Find suppliers →
Is Wärtsilä your company? Claim this page
Wärtsilä

Wärtsilä 34DF

The Wärtsilä 34DF is a medium‑speed, four‑stroke dual‑fuel main engine capable of running on LNG, MDO, HFO or biofuels, delivering up to 500 kW per cylinder (8 000 kW total in the 16‑cylinder version) with intercooled turbocharging.

Wärtsilä Wärtsilä 34DF
Per Hersteller-Datenblatt
Capacity
LNG/MDO/HFO
Medium

Engine Specifications

6L-16V
Cylinders
340 mm
Bore
400 mm
Stroke
4-stroke dual-fuel
Stroke Type

Components & Design

Component data being added…

Technical Data

Power per cylinder (main engine 34DF) 500 kW @ 750 rpm
Power per cylinder (auxiliary 34DF) 520 kW @ 720-750 rpm
Mean effective pressure (main) 20.0-19.8 bar
Piston speed 9.6-10.0 m/s
Compression ratio (16V/20V) 12.6:1
Engine type 4-stroke, turbocharged intercooled non-reversible
Swept volume per cylinder 36.3 dm³
34DF Max output (16V main) 8000 kW
34DF/34SG Max output (20V genset) 9800 kW
34SG design Spark-ignited, lean-burn, pre-chamber
20V34SG dimensions L:12.7m × W:3.3m × H:4.65m
20V34SG weight 131,500 kg
rpm 720/750

🤖 Ask about this model

One free question — answered like a marine engineer. No account needed.

Common failures & inspection points

Turbocharger bearing failure - bearing location pins can break, causing the shaft to rotate freely inside housing and potentially damaging the compressor wheel.
Fuel injector tip carbon deposits and clogging - when operating in backup fuel (diesel) mode, liquid fuel deposits on injector tip can thermally decompose ('cra
Gas valve unit (GVU) functionality criticality - GVU valve tightness and proper ventilation during stop sequences essential for safe operation; leakage prevents
Cylinder liner scuffing from insufficient lubrication - mirror polished finish and loss of crosshatch pattern indicate oil starvation; piston rings run dry caus
Load-sharing failures and abnormal shutdown sequences - improper sensor signals or fuel supply irregularities can trigger emergency stops; root causes (fuel sys

Type-general inspection and maintenance points for this equipment category — not model-specific.

Service & Maintenance

Service schedule includes pilot fuel system, gas admission system and normal cylinder unit inspections.

Suppliers & Spare Parts

Direct links to manufacturer, datasheet, spare-parts portal and dealers — request access below.

📄 Request sourcing links & documents
🛠 Manage this equipment in your fleet

Cases, daily reports, timesheets and AI troubleshooting in the OceanSphere Marine app — free for 14 days.

Start free trial →
🔎 Suppliers & service for this equipment

Find manufacturers, repair shops and spare-part dealers in the Maritime Network — our global company directory.

Maritime Network →

Replacement Parts

Keep pilot injector kits, gas admission valve kits, exhaust valves, filters and electronic sensor spares.
Equipment Model #36801 · ✓ still in production