3806917 Unit Injector Core | Genuine Volvo Penta Part

🔧 Product Description

Core deposit for a unit injector, in the Fuel System group. It is the refundable charge raised against the old unit injector when the exchange unit is bought, and it comes back once the worn unit injector is returned. The line itself is an accounting entry rather than a part, so nothing ships against it on its own. Under Volvo Penta's core numbering the exchange unit it belongs to takes part number 3803917, which is the number to quote for the component itself. We list that number as a unit injector, reman. It is the only line in this block named as a unit injector core, and at 1.27 kg it is far heavier than any of the thirteen plain injector cores here that publish a weight, the largest of which reads 0.544 kg. The exchange unit 3803917 is listed at 1.22 kg, so both sides agree it is a substantial assembly rather than a bare nozzle holder. Several of the plain injector cores in this block pair to counterparts that are themselves listed as unit injectors - 3806928, 3806933 and 3806976 among them - so the naming on the deposit side is not a reliable guide to which kind of injector is involved.

⚙️ Key Features

• Core deposit line, not a unit injector you can fit
• Belongs with the exchange unit, part number 3803917
• Refunded when the old unit injector is returned
• The only unit injector core in this block
• Published weight 1.27 kg
• Exchange unit 3803917 listed at 1.22 kg
• Fuel System group

🔌 Function

As a line item it carries the refundable core charge on the exchange; the unit injector itself combines the pumping element and the nozzle in one body, generating its own injection pressure off the camshaft and metering the shot electronically.

⚠️ 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
• A rough idle with one cylinder plainly doing less work than the rest
• Black smoke, a smell of unburnt diesel and fuel consumption climbing
• A hard knock or rattle from one cylinder that sharpens as the engine warms
• Back-leakage over specification, or a nozzle found dribbling rather than atomising on test

🛠️ Service Notes

• The charge is refunded when the worn unit injector is returned, so keep the old unit and send it back rather than scrapping it
• Ordering this number on its own supplies no part - it goes on the order beside the exchange unit, part number 3803917
• Renew the seals and the copper seat washer with it, and have the injector height and any electrical trim code set to the documented figure once the exchange unit is in

📦 Condition

• Refundable core deposit - not a physical part