1983 Evinrude 6 HP Outboard Specs & Part Numbers
Overview & Specifications
The 1983 Evinrude 6 HP outboard motor (popularly designated by model codes such as E6RCTA for rope start, standard shaft, and E6RLCTA for long shaft) is a highly regarded, twin-cylinder two-stroke marine engine. Produced during the peak of the Outboard Marine Corporation (OMC) era, this motor is famous for its lightweight portability, exceptional idling capabilities, and rugged mechanical design. It is commonly utilized as a primary powerplant for small fishing boats, utility skiffs, and inflatables, or as a trolling “kicker” motor on larger vessels.
| Specification | Details |
|---|---|
| Horsepower | 6 HP @ 4500 RPM |
| Configuration | In-line 2-Cylinder, 2-Stroke |
| Displacement | 8.83 cubic inches / 144 cc |
| Bore & Stroke | 1.9375″ x 1.500″ (49.21 mm x 38.10 mm) |
| Fuel/Oil Mix Ratio | 50:1 (Unleaded 87 Octane / TC-W3 Marine Oil) |
| Weight | Approx. 52 lbs (23.5 kg) for standard shaft |
| Full Throttle Operating Range | 4000 to 5000 RPM |
| Gear Ratio | 12:28 (0.428) |
Common Maintenance & Tune-up Specs
To keep the 1983 Evinrude 6 HP running optimally, routine maintenance must be conducted using correct clearance tolerances and OEM parts. Below are the critical tune-up parameters:
Ignition & Electrical System
- Spark Plug Type: Champion L77JC4 (or QL77JC4 for suppression of radio frequency interference).
- Spark Plug Gap: 0.030 inches (0.76 mm).
- Spark Plug Torque: 17.5 to 20.5 lb-ft (24 to 28 N·m).
- Ignition System Type: OMC Mag 150 CD (Capacitor Discharge) Ignition.
- Points Gap: Not Applicable. The 1983 model utilizes a solid-state, breakerless electronic ignition system. There are no physical points to gap or adjust.
Water Pump & Impeller Information
- Impeller Part Number: OEM #395289 (Sierra equivalent: 18-3051).
- Water Pump Housing: Inspect the stainless steel liner inside the plastic housing for scoring or melting. Replace the housing if wear is present (complete kit: OEM #394711).
- Service Interval: The water pump impeller should be inspected annually and replaced every 2 to 3 seasons, or immediately if the motor has been run dry or exhibits a weak “tell-tale” water stream.
Gearcase & Lubrication
- Gearcase Lubricant: OMC Hi-Vis Marine Gearcase Lube (or any high-quality 80W-90 marine-grade gear lubricant).
- Gearcase Capacity: Approximately 9.0 fluid ounces (266 ml).
- Refilling Protocol: Always pump gear lube in through the bottom drain hole until it flows steadily out of the top vent hole to prevent trapping air pockets in the gear housing. Use new fill/drain plug gaskets (OEM #311598) to prevent water intrusion.
Carburetor Adjustments
- Slow Speed Needle (Idle Mixture): Initial bench setting is 1.5 turns open (counter-clockwise) from a gently seated closed position. Fine-tune in a test tank or on the water with the engine at operating temperature in forward gear. Turn clockwise (lean) until the engine sneezes or stalls, then back out (rich) 1/4 to 1/2 turn for optimal smooth idling.
- High Speed Jet: Fixed orifice jet (non-adjustable). Clean with solvent and compressed air only; do not clear with wire, which can enlarge the brass orifice and ruin fuel calibration.
Notable Features & History
The 1983 Evinrude 6 HP represents a mature iteration of OMC’s compact twin-cylinder platform. By the early 1980s, OMC had refined this motor line to address the primary failure points of older outboards, resulting in one of the most reliable utility engines ever manufactured.
Solid-State CD Ignition
Unlike its predecessors from the 1960s and early 1970s, which relied on mechanical breaker points and magneto coils prone to moisture failure, the 1983 model features a modern Capacitor Discharge (CD) ignition system. This system delivers a hotter spark, virtually eliminates plug fouling at low idle speeds, and ensures consistent, easy starting in cold weather.
Shallow Water Drive & Tilt Features
This motor features a multi-position tilt lock mechanism with a dedicated shallow-water drive setting. This allows boaters to tilt the motor upward slightly, locking the lower unit at an angle to safely navigate through shallow flats, shoals, or weed beds without damaging the propeller or water pump.
Vibration Isolation & Comfort
OMC engineered this model with an advanced rubber mount suspension system (upper and lower motor mounts). These mounts isolate the powerhead’s natural vibration from the steering handle and boat transom, drastically reducing operator fatigue during long trolling runs. The twist-grip throttle on the steering handle provides smooth, intuitive speed control with an integrated steering friction adjustment screw.
Legacy and Parts Availability
The 1983 Evinrude 6 HP shares a vast quantity of interchangeable mechanical parts with brothers in its engine family spanning from 1977 through the late 1990s (including sister brand Johnson 6 HP units). Because millions of these OMC small twins were produced, OEM and aftermarket parts support remains incredibly robust today. Thanks to its simple layout, lightweight footprint, and lack of complex computer electronics, this motor is a favorite among DIY mechanics and vintage marine enthusiasts alike.