8M0097857 Service Kit for Mercury | JLM Marine

8M0097857 Service Kit for Mercury

This comprehensive service kit is designed to fit Mercury outboard engines rated at 75-115 HP with 1.7L displacement, covering serial numbers 1B366823 through 2B094995. It provides all essential components for a complete maintenance overhaul, including impeller, thermostat, fuel filter, oil filter, gaskets, and seals.

Direct Replacement for OEM Part Number: 8M0097857

• Complete maintenance solution with 20+ components including impeller, thermostat, filters, and gaskets
• Includes genuine gear oil pump and all necessary seals for a leak-free installation
• Designed for Mercury 4-stroke outboards in the 75-115 HP range

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here's a guide to help you identify your engine's serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

This service kit includes the following components:

• 817275A2 - Housing x1
• 8M0113262 - Pump base x1
• 8172761 - Plate x1
• 27-8172771 - Gasket x1
• 27-43033-1 - Gasket x1
• 27-43047-2 - Gasket x1
• 8M0050720 - Plate x1
• 47-43026Q02 - Impeller x1
• 43023 - Water tube x1
• 43023 2 - Water tube x1
• 824832 7 - Screw x4
• 2644 - Gasket x4
• 26-830749 - Gasket x3
• 805726 - O-ring x1
• 28-8M0032833 - Key x1
• 8M0090819 - Thermostat x1
• 35-879885Q - Fuel filter x2
• 35-877761K01 - Oil filter x1
• 12-191833 - Gasket x3
• 828816 - Gasket x1
• 24OP149 - Gear Oil Pump x1

Installation Guide

1. Disconnect the spark plug wires and remove the engine cowling to access the powerhead. Ensure the engine is cool and the boat is securely supported.
2. Drain the gear oil using the drain plug at the lower unit. Remove the old oil filter and fuel filters from their housings.
3. Remove the lower unit by disconnecting the shift linkage and unbolting the mounting hardware. Set the lower unit aside on a clean work surface.
4. Remove the water pump housing bolts and carefully separate the housing from the pump base. Discard the old impeller, gaskets, and seals.
5. Clean all mating surfaces thoroughly, removing old gasket material and debris. Inspect for corrosion or damage that may require additional attention.
6. Install the new pump base and secure it with the provided hardware. Place the new impeller into the housing, ensuring the vanes are oriented correctly per rotation direction.
7. Apply a thin layer of marine grease to the impeller vanes to aid initial priming. Install the new water tubes, ensuring proper alignment with the engine block passages.
8. Position new gaskets (27-8172771, 27-43033-1, 27-43047-2) according to the service manual sequence. Install the housing and plates, torquing bolts to manufacturer specifications.
9. Replace the thermostat (8M0090819) in the cooling system housing with a new gasket. Ensure proper seating to maintain correct engine operating temperature.
10. Install the new oil filter (35-877761K01) and both fuel filters (35-879885Q), hand-tightening plus 3/4 turn. Install the gear oil pump (24OP149) and refill the lower unit with fresh gear oil.
11. Reinstall the lower unit to the engine, reconnecting the shift linkage and securing all mounting bolts. Verify shift operation through all gears before final tightening.
12. Replace the engine cowling and reconnect spark plug wires. Start the engine and check for proper water flow from the telltale indicator, leaks, and smooth operation.

Troubleshooting & FAQ

Q: How do I confirm this service kit fits my Mercury engine?
A: Check your engine's serial number plate to verify it falls within the range 1B366823-2B094995 and matches the 75-115 HP, 1.7L specifications. You can also use the Mercury Serial Number Guide to identify your engine model.

Q: How often should I replace the components in this service kit?
A: Mercury recommends replacing the impeller, thermostat, and filters annually or every 100 hours of operation, whichever comes first. If you operate in sandy or debris-laden water, inspect the impeller more frequently for wear.

Q: What are the signs that my water pump impeller needs replacement?
A: Common symptoms include weak or no water flow from the telltale indicator, engine overheating, steam from the engine, or reduced cooling performance. If you notice any of these signs, inspect and replace the impeller immediately.

Q: Can I reuse the old gaskets if they appear to be in good condition?
A: No, always replace all gaskets and seals during service to ensure proper sealing and prevent leaks. Reusing old gaskets can lead to coolant leaks, air intrusion, and compromised water pump performance.

Q: What is the difference between this aftermarket kit and the OEM Mercury kit?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.