3804403 Unit Injector Core | Genuine Volvo Penta Part

🔧 Product Description

Core deposit for a Volvo Penta unit injector, from the Fuel System group. It is an accounting line rather than a fittable part: the refundable charge raised against the old unit injector when a replacement is supplied on exchange, credited back once that worn unit is returned. Ordering it supplies nothing in itself. It is raised against unit 3801403, which our own listing carries as an exchange unit. Core numbers in this series run three thousand above the unit they belong to, so the deposit and the unit are read as a pair.

⚙️ Key Features

• Refundable core deposit on a unit injector, not a fittable part
• Credited back on return of the old unit injector
• Pairs with unit 3801403, three thousand below this core number
• Unit 3801403 is listed here as an exchange unit

🔌 Function

Holds the refundable deposit raised against the old unit injector when a replacement is bought on exchange, and releases it as a credit when that unit is returned. It does no mechanical work. The unit injector itself meters the fuel charge and atomises it directly into its cylinder, pressurised by its own plunger rather than by a separate pump.

⚠️ Common Signs of Failure

• This is a deposit line and has nothing to fail in itself; the signs below are what normally condemns the unit injector being exchanged
• Rough idle, misfire or a knock that traces back to one cylinder
• Hard starting, with white or black smoke hanging at the exhaust
• Fuel getting into the sump, showing as a rising oil level and thin oil
• Nozzle tip coked, eroded or dribbling instead of atomising cleanly

🛠️ Service Notes

• The deposit is refunded when the old unit injector is sent back, so return it complete and as it came off - the credit depends on the core being fit to rebuild, and a stripped or broken-up unit can lose it
• Ordering this line on its own supplies no part. It has to go on the order alongside unit 3801403, which is the item that actually ships
• Several unit injector cores in this block read identically on the line, so the paired unit number is the only dependable way to tell them apart - order by number

📦 Condition

• Refundable core deposit - not a physical part