Part for 4-Stroke Outboards | JLM Marine

Outboard Rubber Impeller with Key / Pin – Fits 4-Stroke 8HP & 9.9HP (209cc)

This aftermarket rubber impeller with key/pin is engineered for 4-stroke outboard engines, specifically the 8HP and 9.9HP (209cc) models. Designed to deliver reliable cooling performance, this impeller ensures your engine operates at safe temperatures during every voyage.

A direct replacement for OEM impellers, this kit provides a cost-effective solution without compromising on quality or fit. Manufactured to OEM specifications, it integrates seamlessly into your existing cooling system.

• Complete kit includes impeller, drive key/pin for immediate installation
• Precision-molded rubber blades for efficient water flow
• Suitable for 4-stroke outboard cooling systems

Compatible Engine Models

Confirm your engine model/year in the table below.

Technical Specifications

Package Contents

• 1 × Outboard Rubber Impeller
• 1 × Drive Key / Pin

Installation Guide

1. Disconnect the fuel line and ensure the engine is off and cool before beginning work.
2. Remove the lower unit from the outboard by unbolting the mounting hardware. Support the unit carefully as you lower it.
3. Access the water pump housing by removing the pump cover plate or housing bolts.
4. Extract the old impeller from the pump housing, noting the orientation of the blades. Remove the old drive key/pin from the driveshaft.
5. Clean the pump housing thoroughly, removing any debris, old gasket material, or corrosion.
6. Lubricate the new impeller blades with glycerin, soapy water, or marine grease to ease installation and prevent tearing.
7. Install the new drive key/pin onto the driveshaft, ensuring it seats properly in the groove.
8. Insert the new impeller into the housing, aligning the blades in the correct rotational direction (typically all blades swept in one direction).
9. Reassemble the pump housing and replace any gaskets or O-rings as needed. Torque bolts to manufacturer specifications.
10. Reattach the lower unit to the outboard, ensuring all mounting bolts are secure.
11. Reconnect the fuel line and run the engine in a test tank or on muffs to verify proper water flow from the telltale (indicator stream).
12. Inspect for leaks around the pump housing and lower unit seals. Correct any issues before operating the engine under load.

Troubleshooting & FAQ

Q: How do I confirm this impeller fits my 4-stroke outboard?
A: Cross-reference your engine's horsepower and displacement with our compatibility table. This impeller is designed for 4-stroke 8HP and 9.9HP (209cc) models. If your model matches, verify the physical dimensions against your original impeller before purchasing.

Q: How often should I replace my water pump impeller?
A: We recommend inspecting your impeller annually and replacing it every 2–3 years or 200–300 hours of operation, whichever comes first. Replace immediately if you notice cracked, brittle, or missing blades, or if your engine runs hot.

Q: What are the signs that my impeller is failing?
A: Common symptoms include weak or absent water flow from the telltale (indicator stream), engine overheating, steam from the engine, or reduced cooling efficiency. If you experience any of these, inspect and replace the impeller promptly.

Q: Do I need to replace the drive key/pin every time I change the impeller?
A: Yes, it's best practice to install a new drive key/pin with each impeller replacement. Worn or damaged keys can cause the impeller to slip on the driveshaft, reducing cooling performance and potentially damaging the pump.

Q: Can I install this impeller myself, or do I need a mechanic?
A: If you have basic mechanical skills and the proper tools, you can install this impeller yourself by following our installation guide. However, if you're unfamiliar with lower unit disassembly or water pump service, we recommend professional installation to ensure safe and correct fitment.

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.