# 1276516 Rubber Cap | Genuine Volvo Penta Part

## 🔧 Product Description

This is the genuine Volvo Penta rubber cap, part number 1276516, used to blank off and seal an unused port on the coolant expansion tank arrangement. It is specified for engines built with keel cooling (KC), where it is fitted together with the expansion tank and secured by hose clamp 961662. Although a very small item, it is a sealing component in the closed coolant circuit and should be renewed whenever the rubber shows hardening or damage.

## 🚤 Compatibility

-   **Engine Family:** D
-   **HP Range:** 30-480 HP
-   **Year Range:** Approximately late 1990s onward

Full model list at the end of this description.

## ⚙️ Key Features

-   OEM Volvo Penta part number 1276516
-   Specified for engines with keel cooling (KC)
-   Fitted in conjunction with the coolant expansion tank and hose clamp 961662
-   Supersedes former part numbers 21920925, 23127054, 23360151, 3580293 and 5753472
-   Fits D1, D4, D6, D9, D11 and D13 series marine diesel engines
-   Engine type: Volvo Penta marine diesel with sump oil extraction tube
-   Also supersedes Volvo part number 3587686

## 🔌 Function

The rubber cap seals an unused connection on the coolant expansion tank, keeping the closed cooling circuit pressure-tight and preventing coolant loss or air ingress. It maintains that seal on keel-cooled installations where the port is not plumbed to a hose.

## ⚠️ Common Signs of Failure

-   Coolant weeping or dripping from the capped port
-   Rubber hardened, perished or cracked with age and heat
-   Cap swollen, distorted or no longer gripping the spigot securely
-   Cap blown off or pushed loose under system pressure
-   Repeated low coolant level or air trapped in the cooling circuit

## 🛠️ Service Notes

-   Fitted only on keel-cooled (KC) engines to blank the unused port on the coolant expansion tank, secured with hose clamp 961662 - not used on raw-water-cooled versions of the same engine
-   Supersedes five earlier numbers (21920925, 23127054, 23360151, 3580293, 5753472); a coolant leak traced to any of those references on old paperwork points to this cap

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   1276516 → Supersedes 21920925 → Supersedes 21505289 → Supersedes 3588990

### OEM / Related Numbers

-   23127054 earlier number superseded by this part
-   23360151 earlier number superseded by this part
-   3580293 earlier number superseded by this part
-   5753472 earlier number superseded by this part
-   21920925 earlier number superseded by this part
-   21505289 earlier number superseded by this part
-   3885197 earlier number superseded by this part
-   3588990 earlier number superseded by this part
-   GAM0011410 supplier catalogue reference

## 📦 Condition

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

## 🔎 Full Model Compatibility

Typically suits:

-   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 D13C1-B MH, D13C4-B MP, D13C5-B MP, D13C8-B MP
-   Volvo Penta D1-30, D1-30B, D1-30F

## Details

- **Price:** 8.92 AUD
- **Vendor:** Volvo Penta
- **Type:** Cooling System
- **Tags:** Volvo Penta Parts | Genuine Marine Engine & Service Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 8.92 AUD | In stock |

## Images

- 1276516 Rubber Cap | Genuine Volvo Penta Part
- 1276516 Rubber Cap | Genuine Volvo Penta Part - photo 2 of 3
- 1276516 Rubber Cap | Genuine Volvo Penta Part - photo 3 of 3

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/1276516-rubber-cap-genuine-volvo-penta)
> Updated: 2026-09-19