2008 Mercury 20HP Short Tiller – 4S (M16898)

2008 Mercury 20HP Short Tiller 4-Stroke outboard motor is a compact and efficient engine designed for small boats. Here’s an overview of its features and specifications: 2008 Mercury 20HP Short Tiller – 4S (M16898)

General Information

• Model Year: 2008
• Manufacturer: Mercury Marine
• Model Number: (M16898 may refer to an internal catalog or listing code)
• Horsepower: 20 HP
• Engine Type: 4-Stroke
• Control Type: Tiller Handle
• Shaft Length: Short (15 inches)

Key Features

Compact Size: Ideal for small boats, dinghies, jon boats, and inflatables.
4-Stroke Efficiency: Quieter operation, better fuel economy, and lower emissions compared to 2-stroke engines.
Tiller Handle Steering: Provides simple and direct control.
Manual Start: Reliable pull-start system (may include an electric start option on some variants).
Lightweight Design: Easier to transport and install, typically weighing around 115 pounds.
Shallow Water Drive: Allows operation in shallow areas without damaging the propeller or lower unit.

Fuel and Oil

• Fuel Type: Unleaded gasoline (87 octane minimum).
• Oil Type: Mercury SAE 10W-30 Marine 4-Stroke Oil.
• Fuel Delivery: Carbureted (check for potential cleaning needs due to varnish buildup in older motors).

Performance and Applications

• Top Speed: Can achieve 20-25 mph depending on the boat size and load.
• Applications: Perfect for fishing, recreational boating, and small watercraft.
• Propeller Options: Aluminum or stainless steel props available for enhanced performance or durability.

Maintenance Notes

Oil Changes: Replace engine oil and filter every 100 hours or annually.
Fuel System: Inspect and replace fuel filters regularly; use a fuel stabilizer if storing the engine.
Cooling System: Flush the engine with freshwater after saltwater use. Replace the impeller every 2-3 years.
Valve Adjustment: Recommended every 300 hours or 3 years (consult the service manual).
Spark Plug Maintenance: Check and replace as needed. Use NGK DPR6EA-9 spark plugs.

Troubleshooting Tips

Engine Won’t Start:

• Check fuel quality and connections.
• Inspect spark plugs for fouling.
• Verify the kill switch and lanyard are properly connected.

Overheating:

• Likely caused by a worn impeller or blocked water intake.
• Inspect and clean the intake screen and replace the impeller.

Rough Idle or Poor Performance:

• Clean or rebuild the carburetor.
• Check for water in the fuel system.

Parts and Accessories

OEM Parts

• Mercury Dealers: Visit a local dealer or Mercury’s website for genuine parts.
• Boats.net or MarineEngine.com: Search for Mercury 20HP 4-Stroke parts by model year.

Aftermarket Parts

• Sierra and Mallory Marine provide high-quality aftermarket parts, such as fuel filters and impellers.