# 990976 Lock Nut | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta lock nut weighing 0.001 kg and listed for 72 D-series applications.

## 🚤 Compatibility

-   **Engine Family:** D
-   **HP Range:** 145-480 HP

Full model list at the end of this description.

## ⚙️ Key Features

-   0.001 kg
-   72 D-series applications
-   Quantity varies by assembly, most commonly four

## 🔌 Function

Holds a threaded joint against vibration, its locking feature resisting the nut turning back once tightened.

## ⚠️ Common Signs of Failure

-   Nut loose or missing at the next inspection
-   Nut spinning down the thread freely by hand
-   Thread crossed or stripped
-   Corrosion between nut and stud

## 🛠️ Service Notes

-   Single use - once released, the locking feature will not hold to the same figure again
-   Lock nuts 990977 at M5 and 990978 at M6 are the thread-marked nuts in this group; no thread size is published for this one, so match it to the stud

## 📦 Condition

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

## 🔎 Full Model Compatibility

Typically suits:

-   Volvo Penta D13C3-B MH, D13C1-B MH, D13C4-B MH, D13C2-B MP, D13B-E MG, D13B-F MG, D13B-N MH, D13C4-B MP, D13C5-B MP, D13C6-A MP, D13C1-A MH, D13C2-A MH, D13C1-B MG, D13C3-B MG, D13C2-B MG, D13C4-B MG, D13C5-A MP, D13C2-A MG, D13C1-A MG, D13C7-B MP, D13C8-B MP, D13C9-A MP
-   Volvo Penta D6-340I-G, D6-380I-G, D6-440I-G, D6-480I-G, D6-300A-G, D6-340A-G, D6-380A-G, D6-440I-WJ-G, D6-480I-WJ-G, D6-300D-G, D6-340D-G, D6-380D-G, D6-440D-G, D6-480D-G, D6-400A-G, D6-440A-G, D6-300I-G
-   Volvo Penta D4-175I-G, D4-230I-G, D4-270I-G, D4-320I-G, D4-300I-G, D4-150A-G, D4-230A-G, D4-270A-G, D4-320A-G, D4-300A-G, D4-145I-G
-   Volvo Penta D8A2-A MP, D8A5-A MH, D8A6-A MH, D8A5-A MG, D8A6-A MG, D8A4-A MP, D8A1-A MP, D8A3-A MP, D8A7-A MP, D8A8-A MP
-   Volvo Penta D16C1-E MG, D16C1-F MG, D16C2-E MG, D16C2-F MG, D16C1-E MH, D16C1-F MH, D16C2-E MH, D16C2-F MH
-   Volvo Penta D11C1-A MP, D11C3-A MP, D11C2-A MP, D11C4-A MP

## Details

- **Price:** 0.56 AUD
- **Vendor:** Volvo Penta
- **Type:** Fasteners & Fixings
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 0.56 AUD | In stock |

## Images

- 990976 Lock Nut | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/990976-lock-nut-genuine-volvo-penta)
> Updated: 2026-09-22