---
product_id: 8437954
title: "MERCRUISER ALPHA ONE UPPER BOX GEARCASE SEAL KIT | GLM Part Number: 87500; Sierra Part Number: 18-2648; Mercury Part Number: 26-32511A1"
brand: "glm marine"
price: "NT$2625"
currency: TWD
in_stock: true
reviews_count: 4
category: "Glm Marine"
url: https://www.desertcart.tw/products/8437954-mercruiser-alpha-one-upper-box-gearcase-seal-kit-glm-part
store_origin: TW
region: Taiwan
---

# Easy installation with OEM fit Precision-engineered seal kit Compatible with Alpha One & #1 models MERCRUISER ALPHA ONE UPPER BOX GEARCASE SEAL KIT | GLM Part Number: 87500; Sierra Part Number: 18-2648; Mercury Part Number: 26-32511A1

**Brand:** glm marine
**Price:** NT$2625
**Availability:** ✅ In Stock

## Summary

> 🛥️ Seal the deal with confidence—keep your Alpha One running smooth and leak-free!

## Quick Answers

- **What is this?** MERCRUISER ALPHA ONE UPPER BOX GEARCASE SEAL KIT | GLM Part Number: 87500; Sierra Part Number: 18-2648; Mercury Part Number: 26-32511A1 by glm marine
- **How much does it cost?** NT$2625 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.tw](https://www.desertcart.tw/products/8437954-mercruiser-alpha-one-upper-box-gearcase-seal-kit-glm-part)

## Best For

- glm marine enthusiasts

## Why This Product

- Trusted glm marine brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Comprehensive Seal Kit:** Includes all essential components for a complete upper box gearcase seal replacement—no extra parts needed.
- • **Trusted by Professionals:** Rated 4.8/5 by 60+ marine enthusiasts who demand quality and precision.
- • **Seamless OEM Compatibility:** Perfectly designed for Alpha One and #1 models up to 1997, ensuring flawless integration.
- • **Durable Marine-Grade Materials:** Built to withstand harsh marine environments, delivering long-lasting performance and reliability.
- • **Cost-Effective Maintenance Upgrade:** Premium quality at a great price, minimizing downtime and maximizing your vessel’s performance.

## Overview

The MERCRUISER ALPHA ONE UPPER BOX GEARCASE SEAL KIT (GLM Part 87500) is a high-quality, OEM-compatible seal replacement kit designed for Alpha One and #1 models up to 1997. Engineered with durable marine-grade materials, it ensures a reliable, leak-proof fit that meets professional standards. Highly rated by users, this kit offers a cost-effective solution for maintaining optimal engine performance and longevity.

## Description

For #1 and Alpha One TO 1997

Review: Nice kit - Good quality gasket kit at a great price. A schematic drawing added for reference would be nice, but still not a complaint as you should have a manual for torque values anyway.
Review: As described. - As described worked good for alpha one gen 2.

## Features

- GLM Part Number: 87500; Sierra Part Number: 18-2648; Mercury Part Number: 26-32511A1

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B004AQZBFO |
| Best Sellers Rank | #430,837 in Automotive ( See Top 100 in Automotive ) #484 in Powersports Seals |
| Brand Name | GLM MARINE |
| Customer Reviews | 4.8 out of 5 stars 60 Reviews |
| Manufacturer | GLM |
| Part Number | 87500 |

## Images

![MERCRUISER ALPHA ONE UPPER BOX GEARCASE SEAL KIT | GLM Part Number: 87500; Sierra Part Number: 18-2648; Mercury Part Number: 26-32511A1 - Image 1](https://m.media-amazon.com/images/I/61Hl-PWgWWL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Nice kit
*by T***. on May 18, 2016*

Good quality gasket kit at a great price. A schematic drawing added for reference would be nice, but still not a complaint as you should have a manual for torque values anyway.

### ⭐⭐⭐⭐ As described.
*by N***I on October 6, 2019*

As described worked good for alpha one gen 2.

### ⭐⭐⭐⭐ Four Stars
*by R***. on September 22, 2015*

Worked well on my 120 HP I drive.

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**Shop now:** [https://www.desertcart.tw/products/8437954-mercruiser-alpha-one-upper-box-gearcase-seal-kit-glm-part](https://www.desertcart.tw/products/8437954-mercruiser-alpha-one-upper-box-gearcase-seal-kit-glm-part)

---

*Product available on Desertcart Taiwan*
*Store origin: TW*
*Last updated: 2026-07-15*