Twin Disc MG506 Marine Transmission Parts Catalog

Introduction: Power, Precision, and Reliability

The Twin Disc MG506 marine transmission is a trusted choice for a wide range of vessels, including commercial fishing boats, workboats, and recreational craft. Renowned for its smooth power transfer, robust design, and reliable performance, the MG506 is engineered to deliver long-lasting service in demanding marine environments.

At Diesel Pro Power, we proudly offer a complete selection of MG506 parts, providing everything you need to keep your transmission running at peak performance. Our extensive inventory ensures fast order processing, worldwide shipping, and expert support to help you maintain your MG506 transmission with confidence.

Rebuilt Twin Disc MG506 Marine Transmissions: Gear Ratios and Applications

At Diesel Pro Power, we offer a range of rebuilt Twin Disc MG506 marine transmissions, meticulously remanufactured to meet OEM standards. Each transmission is available in specific gear ratios to suit diverse vessel requirements, and each rebuilt transmission is for sale.

Twin Disc MG506 Marine Transmission 1.5:1 – Rebuilt for Sale

Ideal for high-speed vessels such as patrol boats and fast ferries, the 1.5:1 ratio provides a balance between speed and torque. This configuration is perfect for applications requiring rapid acceleration and higher cruising speeds.

Twin Disc MG506 Marine Transmission 2.0:1 – Rebuilt for Sale

The 2.0:1 ratio offers a versatile balance between speed and power, making it suitable for commercial fishing boats, workboats, and recreational vessels. It ensures efficient fuel consumption while maintaining adequate thrust.

Twin Disc MG506 Marine Transmission 2.5:1 – Rebuilt for Sale

Designed for vessels needing more torque, the 2.5:1 ratio is commonly used in utility vessels and heavy-duty workboats. This configuration provides enhanced pulling power for towing and demanding operations.

Twin Disc MG506 Marine Transmission 3.0:1 – Rebuilt for Sale

The 3.0:1 ratio delivers maximum torque, making it ideal for tugboats, larger fishing vessels, and heavy-duty applications. This setup ensures reliable performance under substantial loads.

Each rebuilt transmission includes essential components such as:

• Mechanical selector valve assembly (control valve)

• Pilot housing flange

• Oil pump

• Oil level gauge

• Output flange

Note: The drive ring is sold separately.

By choosing the appropriate gear ratio for your vessel, you can optimize performance, fuel efficiency, and operational reliability. All rebuilt MG506 transmissions are for sale and available through Diesel Pro Power for prompt shipping worldwide.

Essential MG506 Parts for Maintenance and Overhaul

Overhaul Plate Kit – For Twin Disc MG506 Transmission

Our overhaul plate kit includes all the brass friction plates and steel plates required for a full clutch rebuild, ensuring smooth engagement and reduced wear.

Gasket Set – For Twin Disc MG506 Transmission

Complete gasket sets with main housing gaskets, O-rings, seal rings, and auxiliary gaskets provide leak-free sealing and reliable performance under high-pressure, high-temperature marine conditions.

Bearing Kit – For Twin Disc MG506 Transmission

The bearing kit features high-quality bearings that reduce friction, maintain alignment, and extend the lifespan of the MG506 transmission.

Ring Kit – For Twin Disc MG506 Transmission

Our ring kit includes essential sealing and retaining rings, restoring system integrity and ensuring smooth operation.

Plate – For Twin Disc MG506 Transmission

Replacement individual brass and steel plates for targeted clutch system repairs, maintaining the performance of the transmission without requiring a complete kit.

Rubber Block (Coupling) – For Twin Disc MG506 Transmission

The rubber block absorbs vibrations, compensates for misalignments, and reduces stress on the transmission and propeller shaft.

Seal – For Twin Disc MG506 Transmission

High-quality input and output shaft seals and dynamic sealing solutions prevent fluid leaks and contamination, protecting internal components.

Oil Pump & Filter – For Twin Disc MG506 Transmission

Ensures continuous lubrication and filtration, maintaining optimal performance and protecting critical internal components from wear and damage.

Gauges – For Twin Disc MG506 Transmission

Accurate pressure and temperature gauges monitor transmission conditions, helping operators detect potential issues early.

Oil Cooler – For Twin Disc MG506 Transmission

The oil cooler regulates temperature, prevents overheating, and extends the life of internal components, constructed from corrosion-resistant materials for marine environments.

Marine Transmission Specifications & Applications of the Twin Disc MG506

Overview of the Twin Disc MG506 Marine Transmission

The Twin Disc MG506 is a mechanically actuated marine transmission built for light- to medium-duty commercial and recreational vessels. Known for its durability, ease of service, and compact design, the MG506 remains one of the most popular mechanical marine gearboxes in the industry. It’s commonly found in fishing boats, workboats, tour vessels, and utility craft operating with diesel engines in the 250–350 horsepower range.

With no electronic control systems and a proven mechanical clutch setup, the MG506 is especially valued in remote or rugged operations where reliability and simplicity are critical. The transmission is available in multiple gear ratios, supports SAE 2 or SAE 3 housings, and is built to handle the torque output of many mid-range marine diesel engines.

Key Specifications of the Twin Disc MG506

• Type: Marine mechanical transmission with hydraulic multi-disc clutch

• Horsepower Rating (Approximate):

• Continuous Duty: Up to 300 HP @ 1800 RPM

• Intermittent Duty: Up to 350 HP @ 2300 RPM

• Max Input Speed: 2500 RPM

• Reduction Ratios Available:

• 1.50:1

• 2.00:1

• 2.47:1

• 2.95:1

• 3.05:1

• Input Housing: SAE No. 2 or SAE No. 3

• Flywheel Compatibility: 11.5", 14"

• Clutch Type: Oil-cooled hydraulic multi-disc clutch, mechanically actuated

• Cooling System: Oil-to-water heat exchanger or oil-to-air cooler (optional)

• Lubrication: Internal lubrication pump with pressure-fed oil system

• Oil Capacity: Approximately 6–8 quarts depending on configuration

• Dry Weight: Approximately 325–375 lbs

• Mounting: Engine-mounted; available with straight or down-angle output

• Rotation Compatibility: Accepts both clockwise and counterclockwise engine rotation

• Optional Features:

• Live PTO (hydraulic or mechanical)

• Trolling valve for precise maneuvering

• Flexible or rigid mounting

Common Marine Applications for the MG506

The MG506 is a versatile transmission well-suited for medium diesel-powered vessels that demand smooth shifting and low-maintenance reliability. It is commonly installed in:

• Commercial Fishing Boats: Widely used in crab, lobster, and gillnet vessels with mid-range diesel engines.

• Patrol and Harbor Boats: Valued for its mechanical reliability and easy service access.

• Tour Boats and Sightseeing Vessels: Popular in ferries and charter vessels needing dependable operation with low vibration.

• Workboats and Utility Craft: Used in line boats, tugs (light-duty), and service craft operating in ports and marinas.

• Recreational Motor Yachts: A favorite for retrofits and new builds in the 35–50 ft range with diesel propulsion.

Most Common Engine Models Paired with the Twin Disc MG506

The MG506 is commonly mated with inline-four and inline-six marine diesel engines delivering 250–350 horsepower. Its mechanical simplicity, SAE housing options, and proven geartrain allow it to integrate easily with a variety of trusted diesel engine brands.

Cummins Marine Engines

• Cummins 6BT / 6BTA 5.9

• Cummins QSB 5.9

• Cummins QSB 6.7
  These Cummins engines are a strong match for the MG506 in commercial fishing vessels and harbor patrol craft, offering excellent torque characteristics and dependable power.

Detroit Diesel Marine Engines

• Detroit Diesel 4-53

• Detroit Diesel 6V53

• Detroit Diesel 6-71 (light rating)
  Often found in refits or legacy vessels, these Detroit models pair well with MG506 transmissions for straightforward, rugged propulsion systems.

Caterpillar Marine Engines

• Caterpillar 3054B / 3054C

• Caterpillar 3116 / 3126 (lower horsepower ratings)
  These engines are ideal for MG506 applications where consistent medium-load propulsion is needed in smaller workboats or transport craft.

Perkins Marine Engines

• Perkins 6.3544

• Perkins M300C
  A common combination in international fleets, especially in commercial vessels operating in coastal or inland environments.

John Deere Marine Engines

• John Deere 4045TFM75

• John Deere 6068TFM50
  Used widely in patrol boats, dredges, and small transport craft, these engines complement the MG506’s performance profile.

Advantages of the Twin Disc MG506

• Mechanical Actuation: No reliance on electronic shift systems—simplified diagnostics and reduced potential failure points.

• Compact & Durable: Designed for long-term use in tight engine rooms with limited service access.

• Wide Ratio Options: Multiple reduction ratios allow fine-tuning for propeller efficiency and hull design.

• Field-Proven Reliability: Ideal for rugged commercial use and remote operations where uptime is critical.

• Simple Installation: Compatible with common SAE housings and flywheel sizes.

Ideal Use Cases for the MG506

Additional Resources

Practical Guide for Twin Disc MG506 (Marine Gear)

Introduction

• Overview of the Twin Disc MG-506 Marine Transmission

• Key Features and Benefits

• Safety Precautions and Warnings
  

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Specifications for Twin Disc 506 Marine Gear

• General Specifications (Weight, Dimensions)

• Technical Specifications (Torque, Power Rating, Gear Ratios)

• Fluid Capacity and Type

• Operating Parameters and Limits
  

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Installation Guide for Twin Disc 506 Marine Gear

• Pre-Installation Checklist

• Tools and Equipment Required

• Mounting Procedures

• Alignment Guidelines

• Fluid Connection Procedures

• Final Inspection Before Initial Operation
  

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Operation Instructions for Twin Disc 506 Marine Gear

• Starting Procedures

• Shifting Instructions (Forward, Neutral, Reverse)

• Normal Operating Practices

• Monitoring and Adjustments During Operation

• Shutdown Procedures
  

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Maintenance Guide for Twin Disc 506 Marine Gear

• Regular Maintenance Schedule

• Lubrication and Fluid Change Intervals

• Inspection of Key Components (Filters, Seals, Clutches)

• Troubleshooting Common Issues (Noise, Vibration, Slippage)

• How to Address Minor Leaks or Adjustments

• Long-Term Storage Guidelines
  

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Troubleshooting and Diagnostics for Twin Disc 506 Marine Gear

• Identifying Common Problems

• Step-by-Step Diagnostic Procedures

• Corrective Actions for Common Failures

• When to Seek Professional Assistance
  

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Rebuilding and Overhaul Basics for Twin Disc 506 Marine Gear

• Symptoms Indicating Rebuild Requirements

• Required Tools and Setup

• Component Disassembly Overview

• Parts Inspection and Replacement Guidelines

• Reassembly Procedures

• Post-Rebuild Testing and Adjustments
  

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Replacement Parts Guide for Twin Disc 506 Marine Gear

• List of Commonly Replaced Components

• Recommendations for Using Premium Aftermarket Parts

• Guidelines for Ordering Replacement Parts

• Compatibility Considerations
  

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Frequently Asked Questions (FAQ)

• What fluids are recommended for the MG-506?

• How often should maintenance be performed?

• How can I identify signs of wear?

• Can I use aftermarket parts for repairs?

• What are common operational mistakes to avoid?

Frequently Asked Questions (FAQs) about the Twin Disc MG506

1. What types of vessels use the Twin Disc MG506 transmission?

The MG506 is used in commercial fishing vessels, workboats, patrol boats, and recreational yachts, offering smooth and reliable power transfer.

2. What essential maintenance parts are available for the MG506?

Diesel Pro Power offers overhaul plate kits, gaskets, bearing kits, ring kits, plates, couplings, seals, oil pumps & filters, gauges, and oil coolers.

3. What’s included in the overhaul plate kit?

The overhaul plate kit contains all the brass friction plates and steel plates needed for a complete clutch rebuild.

4. How do I know when to replace the rubber block (coupling)?

Replace it if you notice increased vibrations, unusual noise, or visible cracks or wear during inspections or maintenance.

5. How often should the oil and filter be changed?

It’s recommended to change the oil and filter every 500 hours of operation or annually, whichever comes first.

6. What type of oil should be used in the MG506 transmission?

Use SAE 30W engine oil for operating temperatures between 150°F and 185°F, and SAE 40W engine oil for temperatures between 185°F and 210°F.

7. Are Diesel Pro’s aftermarket parts reliable for the MG506?

Yes! Our aftermarket parts are designed to meet or exceed OEM standards, ensuring performance and reliability at a competitive price.

8. How quickly can I get MG506 parts from Diesel Pro Power?

Orders are typically processed within 24 hours, with fast global shipping to minimize downtime.

9. What are signs that the MG506 needs an overhaul?

Watch for slipping gears, unusual noises, fluid leaks, overheating, or reduced performance. These are indicators of wear or damage requiring service.

10. Can Diesel Pro Power assist with selecting MG506 parts?

Absolutely! Our team provides expert technical support and installation guidance to ensure you select the right parts for your Twin Disc MG506 transmission.