# 990953 Flange Lock Nut | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta flange lock nut weighing 0.032 kg and listed for 31 applications across the TAD and TWD ranges. It supersedes part number 971100, which was catalogued earlier as a hexagon nut.

## 🚤 Compatibility

-   **Engine Family:** TAD, TWD

Full model list at the end of this description.

## ⚙️ Key Features

-   0.032 kg
-   31 applications across the TAD and TWD ranges
-   Supersedes 971100, earlier catalogued as a hexagon nut
-   Flange and locking feature in one nut
-   Quantity varies by assembly, most commonly 8

## 🔌 Function

Locks a threaded joint with a flange that spreads the load and a locking feature that resists vibration loosening.

## ⚠️ Common Signs of Failure

-   Nut backing off in service
-   Locking feature no longer gripping the thread
-   Flange face flattened
-   Corrosion seizing the nut to its stud

## 🛠️ Service Notes

-   The number it replaces was a plain hexagon nut, so check whether a separate washer was fitted with the original before ordering
-   Single use - fit a new nut whenever the joint is opened

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   990953 → Supersedes 971100 → Supersedes 971073 → Supersedes 961977 → Supersedes 10438

### OEM / Related Numbers

-   971100 earlier number superseded by this part
-   971073 earlier number superseded by this part
-   961977 earlier number superseded by this part
-   10438 earlier number superseded by this part

## 📦 Condition

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

## 🔎 Full Model Compatibility

Typically suits:

-   Volvo Penta TAD1640-42GE-B, TAD1640GE, TAD1640VE-B, TAD1640-42VE-C
-   Volvo Penta TAD1641VE-B, TAD1641GE, TAD1641VE
-   Volvo Penta TAD1642VE-B, TAD1642GE, TAD1642VE
-   Volvo Penta TAD1643VE-B, TAD1643VE
-   Volvo Penta TAD1650VE-B/51VE, TAD1650GE
-   Volvo Penta TAD1341-43GE-B
-   Volvo Penta TAD1344-45GE-B
-   Volvo Penta TAD1351-53VE
-   Volvo Penta TAD1371-75VE
-   Volvo Penta TAD1380-82GE
-   Volvo Penta TAD1381-85VE
-   Volvo Penta TAD1384-85VE-IWP
-   Volvo Penta TAD1651GE
-   Volvo Penta TAD1660-62VE
-   Volvo Penta TAD1662VE EU5
-   Volvo Penta TAD1670-72VE
-   Volvo Penta TWD1644-45GE
-   Volvo Penta TWD1652GE
-   Volvo Penta TWD1653GE
-   Volvo Penta TWD1672-1673GE
-   Volvo Penta TWD1682-83GE
-   Volvo Penta TWD1683VE

## Details

- **Price:** 5.21 AUD
- **Vendor:** Volvo Penta
- **Type:** Fasteners & Fixings
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 5.21 AUD | In stock |

## Images

- 990953 Flange Lock Nut | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/990953-flange-lock-nut-genuine-volvo-penta)
> Updated: 2026-10-07