Drain Hose Assembly – Fits MerCruiser 4.3L, 5.0L, 5.7L Stern Drives (Replaces 32-87108, 32-861590A05)
Drain Hose Assembly – Fits MerCruiser 4.3L, 5.0L, 5.7L Stern Drives (Replaces 32-87108, 32-861590A05) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
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Drain Hose Assembly – Fits MerCruiser 4.3L, 5.0L, 5.7L Stern Drives...
Drain Hose Assembly – Fits MerCruiser 4.3L, 5.0L, 5.7L Stern Drives (Replaces 32-87108, 32-861590A05) is backordered and will ship as soon as it is back in stock.
Product Details
This Drain Hose Assembly is designed for MerCruiser 4.3L, 5.0L, and 5.7L stern drive engines. It serves as a crucial connection from the circulation pump to the thermostat housing within the manual drain cooling system.
It provides a direct interchange for MerCruiser part numbers 32-87108, 32-861590A05, and others, as well as equivalents for OMC, Johnson/Evinrude, and Sierra.
- Connects the circulation pump to the thermostat housing.
- Designed for manual drain cooling systems.
- Manufactured in an ISO 9002 certified facility for quality assurance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 32-87108 |
| MerCruiser | 32-861590A05 |
| MerCruiser | 32-861590A2 |
| MerCruiser | 32-806825 |
| MerCruiser | 32-861590A1 |
| MerCruiser | 33189 |
| MerCruiser | 32-33189A1 |
| OMC/Johnson/Evinrude | 0312781 |
| OMC/Johnson/Evinrude | 0509280 |
| OMC/Johnson/Evinrude | 0910205 |
| Sierra | 18-71337 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For MerCruiser owners, this hose is primarily used in V6 and V8 stern drive models with manual or standard cooling systems. Check your OEM part number to ensure a match.
| Brand | Model | OEM Part No. | Notes |
|---|---|---|---|
| MerCruiser | 4.3L | 32-87108 | Manual drain cooling system |
| MerCruiser | 5.0L | 32-87108 | Manual drain cooling system |
| MerCruiser | 5.7L | 32-87108 | Manual drain cooling system |
| MerCruiser | Black Scorpion 350 Mag MPI | 32-861590A05 | Standard cooling system, manual drain |
Technical Specs
- Product Type
- Drain Hose Assembly
- Installation
- Circulation Pump to Thermostat Housing
- Material
- OEM-specification material
- Connection Type
- Molded
- Color
- Black
- Application
- Manual Drain Cooling System
- Production Standards
- ISO9002 certified factory
What’s in the Box
- 1 x Drain Hose Assembly (32-87108/32-861590A05)
Installation Notes
- Ensure the engine is completely cool and disconnect the battery for safety.
- Place a catch pan under the engine and drain the cooling system.
- Locate the existing drain hose running between the circulation pump and thermostat housing.
- Carefully loosen the hose clamps at both ends and gently twist the old hose to break the seal. Remove it from the engine.
- Clean any residue or corrosion from the connection points on the pump and housing.
- Position the new hose and slide it onto the fittings. Ensure it is not kinked or stressed.
- Securely tighten the hose clamps at both ends. Do not overtighten.
- Refill the cooling system with the appropriate coolant mixture.
- Reconnect the battery, start the engine, and carefully check for any leaks around the new hose connections.
Troubleshooting & FAQ
How can I confirm this hose will fit my engine?
The best way is to verify your engine model and year against the compatibility table. Also, compare your original part's number to the ones listed in our Part Number Matrix. If they match, this hose is a direct replacement.
What are common signs that my drain hose needs replacing?
Look for visible signs of wear such as cracks, brittleness, bulging, or softening of the hose material. Coolant leaks or drips from the hose connections are also clear indicators that a replacement is needed.
How often should this hose be replaced?
There is no fixed replacement interval, but it is good practice to inspect all cooling system hoses during regular seasonal maintenance. We recommend replacing it proactively if it shows any signs of aging or deterioration to prevent engine overheating.
Is there a difference in quality between this and an OEM part?
This is an aftermarket part built to meet or exceed original equipment manufacturer (OEM) specifications. It is made from comparable, high-quality materials in an ISO 9002 certified factory to ensure reliable performance and durability.
Can I install this hose myself?
Yes, this is a part that many boat owners with mechanical experience can replace themselves. However, if you are not comfortable with draining and refilling the cooling system or are unsure about the procedure, we recommend professional installation.
What if the hose leaks after installation?
First, ensure the hose clamps are properly tightened. If a leak persists, the connection surfaces on the engine may be corroded or damaged. If the hose itself is defective, please contact our support for assistance under your warranty.
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.
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