# 3860978 Cylinder | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta hydraulic cylinder from the Marine Propulsion group, weighing 1.084 kg. No engine fitment list is published, but cost records tie it to 17 applications across the B and BB families. It supersedes part number 872598.

## ⚙️ Key Features

-   Marine Propulsion group
-   1.084 kg
-   Supersedes 872598
-   17 applications across B and BB from cost records

## 🔌 Function

Extends and retracts under hydraulic pressure to move the component it is coupled to, and holds that position against load.

## ⚠️ Common Signs of Failure

-   Ram creeping back under load instead of holding position
-   Movement slow, jerky or working in one direction only
-   Oil weeping at the rod seal or from the cylinder end
-   Rod pitted, scored or bent, which will cut a new seal immediately
-   Spongy or noisy operation from air in the system

## 🛠️ Service Notes

-   The other cylinder here, 3860881, is only 64 grams lighter but supersedes a different number and covers a different family list, so check the number on the old unit and order by part number
-   Relieve the hydraulic pressure and support the load before disconnecting, then bleed and cycle the system fully after fitting
-   Inspect the rod and the oil condition before condemning the cylinder

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   3860978 → Supersedes 872598

### OEM / Related Numbers

-   872598 earlier number superseded by this part

## 📦 Condition

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

## Details

- **Price:** 1106.74 AUD
- **Vendor:** Volvo Penta
- **Type:** Drives & Propulsion
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 1106.74 AUD | In stock |

## Images

- 3860978 Cylinder | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/3860978-cylinder-genuine-volvo-penta)
> Updated: 2026-10-21