# 21589402 Adapter | Genuine Volvo Penta Part

## 🔧 Product Description

Sensor/pipe adapter used in the Volvo Penta D9A2A inlet and exhaust installation. Part 21589402 replaces earlier adapter 21554077 and provides the correct threaded interface and insertion position for the associated temperature-sensing hardware.

## 🚤 Compatibility

-   **Engine Family:** D

Full model list at the end of this description.

## ⚙️ Key Features

-   Genuine Volvo Penta threaded adapter
-   Supersedes adapter 21554077
-   Used in D9A2A inlet/exhaust temperature-sensor installation
-   Correct thread, seat and sensor projection
-   Install with the specified gasket and flange screw
-   Engine type: Volvo Penta D9/D11 turbocharged diesel marine engine

## 🔌 Function

Adapts the sensor or adjoining component to the engine pipework while maintaining the correct sealing surface and sensing position.

## ⚠️ Common Signs of Failure

-   Exhaust or boost leakage around the adapter
-   Damaged threads or sealing seat
-   Incorrect temperature readings from poor sensor positioning
-   Cracking or corrosion around the adapter body
-   Repeated gasket failure caused by a damaged mating face

## 🛠️ Service Notes

-   Check the adapter against both of the parts it has to join before fitting — adapters are specific to an engine and its variant, and one that is close but not correct will not seat or seal properly
-   Clean and inspect both mating faces or connector ends; grit, old sealant or corrosion on one side is the usual reason an adapted joint leaks or works intermittently
-   Renew any O-ring, gasket or sealing washer belonging to the joint rather than reusing the old one, and lubricate rubber seals lightly so they slide into place instead of rolling or nipping
-   Tighten threaded adapters to the figure given in the workshop manual for that connection; many go into aluminium or onto a soft seat and will distort if pulled up hard
-   Where the adapter is a workshop tool, check it for thread wear and damage before use and never modify it to make something fit

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   21589402 → Supersedes 21554077 → Supersedes 874330

### OEM / Related Numbers

-   21554077 earlier number superseded by this part
-   21126692 temperature sensor
-   947626 gasket
-   984735 flange screw

## 📦 Condition

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

## 🔎 Full Model Compatibility

Typically suits:

-   Volvo Penta D9A2J, D9A2G, D9A2L MH, D9A2D, D9A2B, D9A2F, D9A2K, D9A2H, D9A2M MP, D9A2A, D9A2C, D9A2E
-   Volvo Penta D11C1-A MP, D11C3-A MP, D11B3-A MP, D11B4-A MP, D11B2-A MP, D11B1-A MP
-   Volvo Penta D16C-A MG, D16C-A MH, D16C-B MH, D16C-C MH, D16C-D MH

## Details

- **Price:** 251.33 AUD
- **Vendor:** Volvo Penta
- **Type:** Inlet & Exhaust
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 251.33 AUD | In stock |

## Images

- 21589402 Adapter | Genuine Volvo Penta Part
- 21589402 Adapter | Genuine Volvo Penta Part - photo 2 of 2

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/21589402-adapter-genuine-volvo-penta)
> Updated: 2026-10-09