Most of the Sulzer A25 engines work in auxiliary power generators on ships, some as stationary power source and many as main propulsion in tugs, floating cranes, fishing ships and other workboats. Fuel type of A25 is MDO only.
In marine environment, machinery such as SULZER 6AL25/30 has to meet higher standards of reliability and greater demands for weight and volume reduction and easier access for maintenance. Marine environment tends toward extreme conditions such as high humidity, sea-water corrosion, vibration and shock due to sea motions.
Sulzer ZL40 is a favorable choice in main ship propulsion modules because its spare parts are widely available. Availability of spare parts reduces the cost and the duration of the execution of maintenance orders.
Sulzer AT25 is a modernized version of Sulzer AS25. AT25 comes with a four valve cylinder head set up which includes 2+2 bore-cooled valves. AT25 can operate both on MDO and HFO while AS25 have two models which can operate either on MDO or HFO. MDO version of AS25 does not have bore-cooling of cylinder head.
Sulzer S20 is a classic 4 stroke engine with number of cylinders ranging from 4 to 9. Sulzer made the journal diameters of this engine sizable to achieve high torsional rigidity. Additionally, S20 offers low operational costs due to easy maintenance and long maintenance intervals.
Sulzer AL20/24 is manufactured in several variants but most commonly manufactured variants are 6 cylinder (6AL20/24) and 8 cylinder (8AL20/24) versions. These engines work as the main engine (propulsion) of small vessels with great results.