1. Applications & Engine Compatibility

This relay architecture is designed around Yamaha’s large-horsepower outboard platforms, primarily serving mid-to-high range V6 engines.

• Horsepower Range: Commonly found on 2-Stroke and early 4-Stroke 150HP, 175HP, 200HP, 225HP, and 250HP engines (including major commercial series like the Yamaha 150A, 200A, and corresponding saltwater variants).

• Cross-Brand Adaptation: Because high-horsepower commercial outboards worldwide heavily rely on this specific electrical blueprint, this relay configuration is standard stock for major aftermarket marine brands (such as Premarine) and serves as a direct replacement component for compatible large-scale platforms.

  
  

2. Key Technical Features & Design Specifications

Engineered to handle intense electrical induction loads while exposed to harsh marine environments, the assembly includes several specialized manufacturing features:

• 12V DC Dual-Directional System: Internally configured to handle high-amp 12V DC switching, reversing polarity cleanly to alternate the trim motor between upward and downward operations.

• Color-Coded Multi-Terminal Block: Features a 4-stud distribution layout under heavy protective hex rubber caps. The terminal posts utilize distinct color-coded index markings (Green, Red, Blue, and Neutral paint indicators) to guide marine technicians and prevent dangerous reverse-wiring during installation.

• Marine-Grade Pigtail Harness: Equipped with an integrated heavy-gauge wire harness terminating in a specialized waterproof, 3-pin female connector block (distinguished by a bright yellow internal weather-pack moisture seal).

• Hermetically Sealed Housing: The entire relay mechanism is encased in an impact-resistant, flame-retardant black composite shell. The solid-state backing plate features dual molded circular relief expansion zones to manage internal heat cycling.

• Rigid Dual-Point Mounts: Integrated top and bottom structural mounting eyelets allow the unit to be securely bolted vertically directly into the outboard's electrical junction bracket inside the engine cowling.

  
  

3. Supply Chain Dynamics & Fleet Maintenance

In the global marine logistics sector, high-amperage relays are classified as critical-tier electrical replacement parts. Because power trim systems draw massive current surges when adjusting an engine under load, the internal contact points inside a relay are naturally subject to electrical arcing, pitting, or eventually welding shut over extended service lifetimes.

When a trim relay fails, the operator completely loses control over the boat’s trim matrix, trapping the motor in a fixed position which heavily degrades fuel efficiency, handling stability, and shallow-water trailering capabilities. Consequently, the 61A-81950-00 remains a vital, high-volume stock asset for international commercial fleets, distributor supply chains, and coastal marine repair operations

OEM Part Numbers

Compatible OEM references include:

• 61A-81950-01-00

• 61A-81950-00

  
  

  
  

Compatible Engine Models

This crankcase assembly is primarily designed for:

• 2-Stroke and early 4-Stroke 150HP

• 2-Stroke and early 4-Stroke 175HP

• 2-Stroke and early 4-Stroke 200HP

• 2-Stroke and early 4-Stroke 225HP

• 2-Stroke and early 4-Stroke 250HP

  
  

  
  

It is also widely used in compatible engines based on the Yamaha, including selected models from:

• Parsun

  
  

If you are unsure about compatibility, please provide your engine model number or identification plate for verification before ordering.

Applications

This Power Trim & Tilt (PTT) Relay is commonly used for:

• Outboard engine repair

• Engine rebuilding projects

• Marine maintenance workshops

• Boat fleet maintenance

• Commercial fishing vessels

• Recreational boats

• Marine spare parts distribution