# 20478064 Hollow Screw | Genuine Volvo Penta Part

## 🔧 Product Description

OEM fastening component used in the low-pressure fuel supply, return and injection-pump connection system. It restores the specified thread, length, strength and clamping arrangement required by the original Volvo Penta assembly.

## 🚤 Compatibility

Typically suits:

-   Volvo Penta D12D-A MG
-   Volvo Penta D12D-E MG
-   Volvo Penta D12D-E MP
-   Volvo Penta D12D-F MP
-   Volvo Penta D12D-H MP
-   Volvo Penta TWD1240VE
-   Volvo Penta TAD1241GE
-   Volvo Penta TAD1242GE
-   Volvo Penta TAD1250VE
-   Volvo Penta TAD1251VE
-   Volvo Penta TAD1252VE
-   Volvo Penta TAD1250-52VE
-   Volvo Penta TAD1240GE
-   Volvo Penta TAD1241VE
-   Volvo Penta TAD1242VE
-   Volvo Penta TAD1241-42VE

-   **Engine Family:** D, TWD, TAD
-   **HP Range:** Approximately 300 HP
-   **Year Range:** Approximately late 1990s-2010s, depending on engine and installation

## ⚙️ Key Features

-   0.059 kg
-   Supersedes 20397814
-   For the low-pressure fuel supply, return and injection-pump connection system
-   Listed for 16 applications across D, TWD and TAD series engines

## 🔌 Function

Acts as a union bolt in the low-pressure fuel system, clamping a pipe eye to its port while passing fuel through its central drilling.

## ⚠️ Common Signs of Failure

-   Fuel weeping from under the pipe eye or around the head
-   Diesel smell and a damp, dirt-collecting patch at the joint
-   Air drawn into the fuel system, causing hunting or hard starting
-   Central drilling found blocked with debris
-   Sealing washers found flattened and hard, and the head found rounded on removal

## 🛠️ Service Notes

-   Always fit new sealing washers each side of the pipe eye - the washers, not the screw, are usually why the joint weeps
-   Check the central drilling is clear before refitting, and do not over-tighten; a stretched hollow screw will snap in service
-   It replaces 20397814, so the two numbers describe the same hollow screw

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   20478064 → Supersedes 20397814

### OEM / Related Numbers

-   20397814 earlier number superseded by this part

### Aftermarket / Verified Equivalents

-   ATP: HS-064

## 📦 Condition

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

## Details

- **Price:** 22.84 AUD
- **Vendor:** Volvo Penta
- **Type:** Fasteners & Fixings
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 22.84 AUD | In stock |

## Images

- 20478064 Hollow Screw | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/20478064-hollow-screw-genuine-volvo-penta)
> Updated: 2026-10-11