Control system for forward-reverse clutches and low pressure supply line

For use in a vehicle or a vessel having a fluid-actuated forward clutch and a rearward clutch, a source of fluid under pressure, and a forward-rearward select valve therebetween, the combination of single lever clutch control system for selectively controlling actuation of the clutch comprising:

• a pressure preserve valve (17);
• a first passageway (2) between said source of pressurized fluid and said valve (17);
• a second passageway (5) between said valve (17) and said select valve (26);
• a one-way control valve (18);
• a third passageway (3) between said passageway (2) and said valve (18);
• a fourth passageway (4) between valve (18) and lubricating parts (19);
• an inching valve (21) the setting pressure of which is regulated in proportion to the extent of action of select valve (26);
• a fifth passageway (9) between passageway (5) and inching valve (21):
• a drain valve (23);
• a sixth passageway (10) between inching valve (21) and drain valve (23);
• and
• a seventh passageway (11) between drain valve (23) and said fourth passageway (4);
• said drain valve (23) being adapted to place said sixth passageway (10) in communication with said seventh passageway (11) when the fluid pressure in fifth passageway (9) increases beyond a pre-determined value whereby inching valve (21) and select valve (26) are operated by a single select lever (27).