The Advance GW series marine gearbox is a product produced by introducing the technology of Lohmann Stoldford Company ofGermany. After more than 30 years of digestion, absorption, optimization and design, there are 6 types including the model of GWc,GWD, GWS, GWH, GWL and GWK series, of which GWC is the base type. The transmission capacity covers 0.257kw/rpm-35.4kw/rpm.This series of products has reliable performance and easy operation. It is the best partner for medium-speed diesel engines at home andabroad. This series of products has complete specifications and high market share, and is widely used in various large ships such as various transport ships, engineering ships, and fishing ships.
The Advance GWC49.54 series marine gearbox has 2-stage reduction. The input and output are concentric and run in the samel direction. It has reverse, clutch and deceleration functions. The product has the characteristics of compact structure, small size and smooth operation.
In this article, we mainly explain how to change the gear ratio of GWC4.9.54 gearbox.
To change the gear ratio of gearbox, just need to change some of the input gears and clutch system accessories, which are the red area in the below drawing.
Following below steps:
1. Disassembly the upper case and the middle case of the gearbox:

2. Take out the input gear set, replace the pointed gear:

3. Take out the clutch accessory, replace the pointed gear:

Don’t change or remove any of the other gears or accessories. Put every back, and its done.
Here we recommend to you several other engines in the GWC series:
The input speed range of the Advance GWC Series Marine Gearbox is 200-2000 RPM, with engine input power is 290-70000 kW at 200-2000 RPM. The reduction ratio range is 1.97-7.49 and transfer capacity range is 35-0.29 kW/RPM.
Advance GWC series marine gearbox is composed of Input coupling, cooler, output coupling, Controller, oil filter, oil pressure gauge and other important components. Advance GWC series marine gearbox controller can be selected pneumatical or electrical operation with manual emergency control device. Advance GWC series marine gearbox are tow stage deceleration, the input and output are concentric, the running direction is the same, and it has the function of reverse clutch deceleration.
These include all engines of the GW series, which may meet your needs:
Advance GW Series Marine Gearbox products can be divided into GWC series, GWD series, GWS series, GWH series, GWL series.
Thanks to their compact design and wide matching range,Advance GW Series Gearbox Its rated output speed is 150-2000r/min, the reduction ratio range is 1.94-7.48, and the rated transmission capacity is 0.29-35.429kw/r/min This series of products is manufactured by Advance with the license technology introduced by German Lohmann Company, and after more than 30 years of digestion, absorption and optimization design, it is mainly used in large bulk carriers, ocean fishing vessels, oil tankers, ships, etc. The product has reliable performance and convenient operation, and is the best partner for medium-speed diesel engines at home and abroad.
As an official marine power pack packager of Advance, SeaMac provide complete propulsion system and power system for all kinds of ships all around the world. Mainly including marine engine, gearbox, shaft, propeller, marine genset, electric control lever system and other marine accessories. We also provide full life cycle services for all our customers, from design to power system supply, from installation to commissioning, from after-sales service training to spare parts supply, from trouble shooting to overhaul technical support.