# 21246119 By-Pass Valve | Genuine Volvo Penta Part

## 🔧 Product Description

A coolant bypass valve used in the water-pump and thermostat-housing circuit on a broad selection of Volvo Penta D13 marine engines. It controls internal coolant circulation while the main thermostat changes position.

## 🚤 Compatibility

-   **Engine Family:** D

Full model list at the end of this description.

## ⚙️ Key Features

-   Controls coolant bypass flow
-   Supports even engine warm-up
-   Works with the specified thermostat and housing seals
-   Direct replacement where part number 21246119 is specified
-   Engine type: D13 inline-six turbocharged marine diesel

## 🔌 Function

Regulates coolant bypass flow during warm-up and thermostat operation.

## ⚠️ Common Signs of Failure

-   Engine warms too slowly
-   Localised overheating
-   Unstable coolant temperature
-   Valve stuck open or closed
-   Coolant-flow noise or restricted circulation

## 🛠️ Service Notes

-   Note the orientation and the port connections before removal; a bypass valve fitted the wrong way round will not regulate at all
-   These are set assemblies rather than adjustable parts — renew the valve rather than attempting to alter its setting
-   Check the seat and bore in the housing for debris, scoring and wear and clean the passages; grit holding a valve part-open is a common fault
-   Renew the seals, O-rings or sealing washers and tighten to the figures in the workshop manual for your engine
-   Run up afterwards and confirm normal system pressure or temperature behaviour, and investigate the cause if the old valve had failed open

## 🔄 Supersession & Cross Reference

### OEM / Related Numbers

-   3889622 - thermostat housing
-   18813 - gasket
-   946086 - plug
-   949659 - O-ring
-   21412639 - thermostat

## 📦 Condition

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

## 🔎 Full Model Compatibility

Typically suits:

-   Volvo Penta D13C2-B MP, D13C1-A MP, D13C2-A MP, D13C3-A MP, D13C4-A MP, D13B-A MP, D13B-H MP, D13B-G MP, D13B-L MP, D13B-E MG, D13B-E MG (FE), D13B-E MH, D13B-E MH (FE), D13B-F MG, D13B-F MG (FE), D13B-K MP, D13B-N MH, D13B-N MH (FE), D13B-B MP, D13B-D MP, D13B-J MP, D13B-M MP, D13B-C MP, D13C4-B MP, D13C5-B MP, D13C6-A MP, D13C1-A MH, D13C2-A MH, D13C1-B MG, D13C3-B MG, D13C5-A MP, D13C2-A MG, D13C1-A MG, D13C7-B MP, D13C8-B MP, D13C9-A MP

## Details

- **Price:** 228.15 AUD
- **Vendor:** Volvo Penta
- **Type:** Cooling System
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 228.15 AUD | In stock |

## Images

- 21246119 By-Pass Valve | Genuine Volvo Penta Part
- 21246119 By-Pass Valve | Genuine Volvo Penta Part - photo 2 of 2

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/21246119-by-pass-valve-genuine-volvo-penta)
> Updated: 2026-10-10