680B Stern Drive

680B Sterndrive

Analysis Form

Every application is analyzed and approved by Konrad Application Engineers.  Please complete the Analysis Form and submit it online, or download the PDF to print, scan, email, or mail back to Konrad.  A Konrad Application Engineer will contact you to discuss your priorities and goals and determine the best Konrad sterndrive model for you.  You can also reach out to us anytime. We look forward to working with you!

Technical Information

For your convenience, we have downloadable documents that will help with the conversion process.

- 600B Series Installation Guide

- 600B Series Maintenance Manual





The Konrad 680B has been engineered with the largest and strongest gears in the industry. The 680B is capable of carrying capacities up to 8.4 metric tons (over 18,500 lbs.) per drive. This drive operates with extreme efficiency in the area of 40 knots (46 mph):

intended for military, commercial, medium duty, and recreational performance the konrad 680B offers

  • Oversized bearings

  • Thicker walled casings

  • Dual, counter rotating propeller

  • Continuous oil circulation for cool operation

  • No corrosive exhaust through drive

  • Precision machined super alloy gears

  • No failure-prone cone clutch

  • Minimal maintenance required

Package Options

Standard Equipment (Supplied with Sterndrive)

  • Complete sterndrive assembly
  • Inner and outer transom assembly
  • Digital trim display and Trim pump assembly
  • Oil reservoir with low level sensor for use in hull
  • Drive comes full of sterndrive lubricant
  • Two quarts of power trim fluid
  • Transom mounted; integrated trim and steering cylinders

Additional Equipment Required (Not supplied but available for purchase from Konrad)

  • Transmission
  • Propeller
  • Steering package
  • Drive shafts/transmission tail piece
  • Bellhousing adapter
  • Flywheel coupling
  • Transmission oil cooler
  • Alignment tool

Options for Individual Applications (Available for purchase from Konrad)

  • Dual Helm kits
  • Isolator Mounts
  • Installation tool kit
  • Extension kits
  • Tie bars
  • Stand off boxes
  • Technical engineering assistance

Material / Manufacturing Specifications

Taper roller bearings, spaced for optimum load carrying capabilities, support the shafts

Manufactured from high strength, heat treated aluminum

High strength heat treated alloy steel utilizing high performance marine technology

Manufactured from high alloy, heat treated steel

Industry leading size for increased load carrying capacity and extended life

Installation / Operational Specifications

Recreational or Commercial

Engine Connection
Direct or Remote (Jack or CV Shaft)

None through the sterndrive

Gear Ratios
1.24:1, 1.43:1, 1.52:1, 1.74:1, 1.94:1

Full Immersion, eighteen quarts with external reservoir

Diameter Range - 15 in - 18.5 in (38 cm - 47 cm)

Counter rotation

Steering Angle
50° range

Reversing transmission required

Transom Mounting
Template available per application

Transom Requirements
13° angle nominal, 6.4 mm - 79.4 mm (1/4 in - 3 1/8 in) thick

Trim/Lift System
Approximate -6° to +10° trim, twin cylinders with electro-hydraulic pump
Approximate 30° of total lift range

Water Pickup
None through the sterndrive


All applications and warranties are subject to evaluation and approval by the factory and may be approved with lower annual hours than noted maximum.

All sterndrive plus engine application will be assigned a Maintenance Schedule "A", "B", or "C", depending on their usage characteristics, which must be followed to ensure warranty coverage.

Warranty and Maintenance Schedules