# 8M0084523 Mercruiser Alternator | Genuine Used Part

## 🔧 Product Description

**Genuine MerCruiser 1.7L DTI 12V 50A Alternator - Part Number: 8M0084523**

A genuine used MerCruiser alternator for Cummins MerCruiser Diesel and MerCruiser 1.7-litre DTI four-cylinder marine engines.

This Mitsubishi-style internally regulated alternator uses a six-groove serpentine pulley and produces a 50-amp output. It is fitted to MI 120 inboard, MS 120 sterndrive and D1.7L DTI Alpha engine packages.

## ⚙️ Key Features

-   Genuine used MerCruiser diesel alternator
-   12-volt, 50-amp output
-   Six-groove serpentine pulley
-   Internally regulated and internally cooled design
-   Fits Isuzu-based 1.7L four-cylinder MerCruiser diesel engines

## 🚤 Compatibility

### Commonly used on

-   Cummins MerCruiser Diesel 1.7L engine charging systems
-   Isuzu-based D1.7L DTI Alpha sterndrive and inboard installations

### Typically suits

-   Engine models:
-   MerCruiser D1.7L DTI Alpha - 2001 onward
-   Cummins MerCruiser Diesel MI 120 1.7L inboard - 2004
-   Cummins MerCruiser Diesel MI 120 1.7L inboard - 2005
-   Cummins MerCruiser Diesel MS 120 1.7L sterndrive - 2004
-   Cummins MerCruiser Diesel MS 120 1.7L sterndrive - 2005
-   CMD 1.7 MI 120 L/L4
-   CMD 1.7 MS 120 L/L4
-   Output: 12V / 50A
-   Engine Type: Cummins MerCruiser Diesel / MerCruiser 1.7L four-cylinder diesel
-   Year Range: Approximately 2001-2005

## 🔌 Function

The alternator converts crankshaft rotation into regulated electrical current for battery charging, engine shut-down controls, instrumentation, glow-plug support circuits and onboard accessories.

## ⚠️ Common Signs of Failure

-   Diesel engine battery loses charge
-   Charge warning lamp remains illuminated
-   Voltage remains near battery resting voltage while running
-   Alternator bearing or pulley becomes noisy
-   Serpentine belt slips or produces black dust
-   Tachometer or charge-dependent instruments behave erratically
-   Output terminal or wiring shows signs of overheating

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   8M0084523 → Supersedes 882571
-   882571 earlier MerCruiser alternator reference

### OEM / Related Numbers

-   8M0084523
-   882571
-   Mitsubishi: A7TA2991
-   Isuzu: 8972477180
-   Arrowhead: AMT0204
-   Lester: 12630
-   J&N: 400-48061

### Aftermarket / Verified Equivalents

-   Sierra: 18-6948
-   Recmar: REC882571
-   Marine Spare Parts: AM882571
-   DB Electrical: 400-48061
-   EMP: 4-6948
-   WAI: 12630N
-   Arrowhead: AMT0204

## 📦 Condition

-   Genuine used part
-   Removed from running engine where applicable
-   In good working condition unless otherwise stated

## Details

- **Price:** 300.0 AUD
- **Vendor:** Sawley's Auto and Marine
- **Type:** Charging & Alternators
- **Tags:** Sawley’s AAM Used Parts – Alternators | Marine Charging Systems & Alternators

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 300.00 AUD | In stock |

## Images

- 8M0084523 Mercruiser Alternator | Genuine Used Part
- 8M0084523 Mercruiser Alternator | Genuine Used Part - photo 2 of 4
- 8M0084523 Mercruiser Alternator | Genuine Used Part - photo 3 of 4
- 8M0084523 Mercruiser Alternator | Genuine Used Part - photo 4 of 4

---

> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/8m0084523-mercruiser-alternator-genuine-used-part)
> Updated: 2026-09-06