479690 Leak-Off Line | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta leak-off line from the Fuel System group, weighing 0.05 kg and listed for 8 applications across the TWD, THD, TD and DH series. It supersedes part number 978879, catalogued earlier as a tube.

🚤 Compatibility

Typically suits:

• Volvo Penta TWD1030ME
• Volvo Penta TWD1031VE
• Volvo Penta THD102KB
• Volvo Penta THD102KD
• Volvo Penta THD102K-KB
• Volvo Penta TD100G
• Volvo Penta TD1030VE
• Volvo Penta DH10A

• Engine Family: TWD, THD, TD, DH

⚙️ Key Features

• 0.05 kg
• 8 applications across the TWD, THD, TD and DH series
• Supersedes 978879, formerly listed as a tube
• Leak-off line 477901 is the other line in this range at 0.041 kg

🔌 Function

Returns the small volume of fuel that leaks past the injector needles back to the tank or return circuit.

⚠️ Common Signs of Failure

• Diesel weeping around the injector tops or under the rocker cover
• Fuel smell in the engine space after a run
• Hard starting or rough running as air enters the return circuit
• Line found cracked, hardened or chafed at a bend
• Sealing washers at the connections found flattened

🛠️ Service Notes

• Renew the sealing washers at every leak-off connection, as they are the usual source of the leak rather than the line itself
• Leak-off line 477901 at 0.041 kg covers a different set of applications, so check the fitment before ordering

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 479690 → Supersedes 978879

OEM / Related Numbers

• 978879 earlier number superseded by this part

📦 Condition

• Genuine Volvo Penta part
• Brand new
• Supplied in original or equivalent packaging