# 21839149 Pulley | Genuine Volvo Penta Part

## 🔧 Product Description

Factory belt-drive pulley supplied as the later replacement for Volvo Penta pulley 20509134. Its groove profile, offset and mounting geometry maintain correct belt alignment.

## ⚙️ Key Features

-   Factory groove profile
-   Correct pulley offset
-   Maintains accessory-belt alignment
-   Supersedes 20509134
-   Use with the specified belt and hub hardware
-   Engine type: Volvo Penta diesel engine

## 🔌 Function

Transfers crankshaft or accessory-drive rotation through the belt while maintaining the required speed ratio and belt tracking.

## ⚠️ Common Signs of Failure

-   Belt running off-centre
-   Worn or damaged grooves
-   Visible wobble or run-out
-   Repeated belt fraying
-   Loose or damaged mounting bore

## 🛠️ Service Notes

-   Inspect the belt running surfaces before fitting — a pulley with glazed, scored, pitted or rust-roughened grooves will chew through a new belt in very little running time
-   Check that the pulley runs true and that its bearing or bush turns smoothly with no roughness or side play; fit a new belt whenever a pulley is changed
-   Confirm that every pulley in the drive lies in the same plane and that the belt profile matches each groove — misalignment shows up as belt dust, squeal or a worn belt edge and will destroy a new belt quickly
-   Fit onto a clean, dry, burr-free shaft or hub face and tighten the retaining fasteners in the sequence and to the figures given in the workshop manual for your engine
-   Turn the engine over by hand before starting to confirm the belt is fully seated in every groove and that nothing fouls, then recheck belt tension after the first running period

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   21839149 → Supersedes 20509134

### OEM / Related Numbers

-   20509134 earlier number superseded by this part
-   3801619 related reference

## 📦 Condition

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

## Details

- **Price:** 835.2 AUD
- **Vendor:** Volvo Penta
- **Type:** Belts, Pulleys & Tensioners
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 835.20 AUD | In stock |

## Images

- 21839149 Pulley | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/21839149-pulley-genuine-volvo-penta)
> Updated: 2026-10-08