100 Hour Maintenance Kit – Fits Mercury 40-60 HP EFI 4-Stroke (Replaces 8M0090558)
100 Hour Maintenance Kit – Fits Mercury 40-60 HP EFI 4-Stroke (Replaces 8M0090558) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
100 Hour Maintenance Kit – Fits Mercury 40-60 HP EFI 4-Stroke (Repl...
Product Details
This 100 Hour Maintenance Kit – Fits Mercury 40-60 HP EFI 4-Stroke (Replaces 8M0090558) provides the essential components for a complete 100-hour service on Mercury 40-60 HP EFI 4-stroke outboard motors (2002–present). The kit includes filters, spark plugs, and gear lube to help maintain optimal engine performance and reliability.
It serves as a direct aftermarket replacement for Mercury part numbers 8M0090558 and the current 8M0232733.
- Includes key components needed for a standard 100-hour service interval.
- Fitment is for specific non-Bigfoot Mercury/Mariner EFI models from 2002 to present.
- All parts are designed to meet or exceed OEM specifications for fit and function.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Mercury | 8M0090558 | 8M0232733 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | EFI (3 Cylinder) | 40 | 4-Stroke | 2002–present | 8M0090558 | Non-Bigfoot models |
| Mercury | EFI (4 Cylinder) | 50 | 4-Stroke | 2002–present | 8M0090558 | Non-Bigfoot models |
| Mercury | EFI (4 Cylinder) | 60 | 4-Stroke | 2002–present | 8M0090558 | Non-Bigfoot models |
Technical Specs
- Product Type
- 100 Hour Maintenance Kit
- Installation
- Standard Service Procedure
- Fuel Type
- Gasoline (87 octane minimum)
- Connection
- Multiple (varies by component)
- Housing Color
- Multiple (varies by component)
- Package Dimensions
- 33.0 cm x 23.0 cm x 17.0 cm (L x W x H)
- Weight
- 0.36 kg (12.8 oz)
- Fitting Type
- Multiple (varies by component)
- Thread Size
- Multiple (varies by component)
- Service Interval
- Designed for OEM-recommended 100-hour service interval
What’s in the Box
- 1 x Oil Filter (35-8M0162829)
- 1 x Fuel Filter (35-879885Q)
- 1 x Inline Fuel Filter (35-879884T)
- 3 x Spark Plug (33-883323001) (Note: 4-cyl models require one extra plug)
- 1 x Premium Gear Lube (equivalent to 92-802844Q1)
Installation Notes
- Before starting, consult your owner's manual for specific procedures and safety precautions.
- Gather necessary tools, including an oil filter wrench, spark plug socket, and a gear lube pump.
- Place a drain pan under the lower unit. Disconnect the engine's kill switch lanyard.
- Drain the engine oil completely and replace the old oil filter with the new one. Lightly oil the new filter's gasket before installing.
- Locate and replace both the primary and inline fuel filters. Note the direction of fuel flow.
- Remove the old spark plugs, check the gap on the new plugs, and install them. Do not overtighten.
- Drain the old gear lube by removing the upper and lower vent screws. Pump in new gear lube from the bottom hole until it flows from the top hole, then replace screws.
- Refill the engine with the correct type and amount of new oil.
- Clean up any spills, re-attach the kill switch lanyard, and start the engine. Check for any leaks from the filters or drain plugs.
Troubleshooting & FAQ
How do I confirm this kit fits my specific engine?
This kit is designed for Mercury/Mariner 40, 50, and 60 HP EFI 4-Stroke outboards (non-Bigfoot models) manufactured from 2002 to the present. Please review the compatibility table and compare the listed OEM part numbers to your engine's service manual.
Does this maintenance kit include engine oil?
No, engine oil is not included. The required oil type (e.g., 10W-30, 25W-40) and quantity vary, so it must be purchased separately based on your owner's manual recommendations.
The kit has three spark plugs, but my engine is a 4-cylinder. Is this correct?
This kit is designed to cover 3-cylinder (40 HP) and 4-cylinder (50/60 HP) models. It contains three spark plugs. If you have a 4-cylinder engine, you will need to purchase one additional spark plug separately.
What is the recommended service interval for this kit?
This kit is intended for the 100-hour or annual service interval, whichever comes first. Regular maintenance is critical for engine longevity and performance.
What are common signs that my outboard needs this 100-hour service?
Aside from tracking engine hours, signs include difficulty starting, rough idling, reduced power, decreased fuel efficiency, or unusual engine noises.
Are any special tools required for installation?
You will need standard mechanic's tools, plus an oil filter wrench, a spark plug socket with an extension, and a gear lube pump to properly fill the lower unit.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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