ZF 400 Series User Manual

Introduction
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1.5 Operating principles
The main functions of a marine reverse transmission include:
• coupling the engine with the propeller axle and reducing the propeller speed;
• inverting the direction of motion;
• interrupting the movement of the propeller shaft (idling mode).
Below is a simplified diagram of the hydraulics.
The marine gearbox allows for obtaining the following three types of operation:
Neutral
The output shaft (2) connected to the propeller axle does not transmit any rotation.
The clutches are disengaged.
Engine rotation
The output shaft (2) connected to the propeller axle rotates in the same direction as the input shaft (1).
Counter engine rotation
The output shaft (2) connected to the propeller axle rotates in the opposite direction to the input shaft (1).
The concordant and/or discordant motion transmission occurs with the transmission ratio indicated on the identifica-
tion plate.
The three operating modes are controlled by the oil control block (3) (mechanical or electrical).
Fig. 2

ZF 400 Series Specifications

General

Type	Marine Transmission
Series	400 Series
Manufacturer	ZF
Application	Marine
Max Input Power	Varies by model (Consult ZF specifications)
Rated power (hp)	Varies by model (Consult ZF specifications)
Max Input Speed	Varies by model (Consult ZF specifications)
Gear Ratios	Varies by model (Consult ZF specifications)
Weight (kg)	Varies by model (Consult ZF specifications)
Weight (lbs)	Varies by model (Consult ZF specifications)
Mounting	Varies by model (Consult ZF specifications)
Housing Material	Aluminum
Oil Capacity (L)	Varies by model (Consult ZF specifications)
Oil Capacity (US qt)	Varies by model (Consult ZF specifications)
Cooling System	Integrated oil cooler (optional external cooler)