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Massey Ferguson 6180, 6190 hydraulic system - Auxiliary spool valves

MF 6100-6200 Series Tractors Repair Operations

The Rexroth SM12 auxiliary spool valves are fitted on the high flow rate circuit. They are fed by oil coming from the trailer braking valve or the closing plate fitted in its place (depending on version).

When the spool valves are not activated, the oil is available for the lift control valve fitted downstream. The Massey Ferguson 6180, 6190 tractor auxiliary spool valves are mounted on a support which is itself fitted to the rear of the lift cover.

Quick-disconnect couplings are fitted directly on the spool valve body. To obtain sufficient distance between couplings, the spool valves are fitted with blocks serving as spacers. These blocks are also used to let the oil flow to the next spool.

Available sets of MF 6180, 6190 spool valves

Set A - 2 spool valves

- Spool valve 1 and 2: 3-position, SA / DA with spring loaded return to neutral

Set B - 2 spool valves and flow divider

- Spool valve 1: 3-position, SA / DA with automatic return to neutral
- Spool valve 2: 4-position, DA with automatic return to neutral

Set C - 2 spool valves and flow divider

- Spool valve 1: 3-position, SA / DA with automatic return to neutral
- Spool valve 2: 3-position, SA / DA and zero leakage

Set D - 3 spool valves and flow divider

- Spool valve 1: 3-position, SA / DA with spring loaded return to neutral
- Spool valve 2: 3-position, SA / DA with automatic return to neutral and zero leakage
- Spool valve 3: 4-position, DA with automatic return to neutral

Set E - 3 spool valves and flow divider

- Spool valve 1: 3-position, SA / DA with automatic return to neutral
- Spool valve 2 and 3: 4-position, DA with automatic return to neutral

Set F - 4 spool valves and flow divider

- Spool valve 1: 3-position, SA / DA with spring loaded return to neutral
- Spool valve 2 and 3: 3-position, SA / DA with automatic return to neutral and zero leakage
- Spool valve 4: 4-position, DA with automatic return to neutral

(1) Inlet unit with flow control valve (2) Plates with seals (3) Excess flow rate pipe (4) Adjustment knob (flow divider) (5) Single / double acting (SA / DA) change-over screw (6) Spool valves (all versions) (7) Intermediate block (excess flow rate) (8) Set (2, 3 or 4 spool valves) (9) Intermediate block (10) Support (11) End plate (connection with lift control valve) (12) Screw (13) Plug and seal (provisional return) (14) Screw (15) Cap and seal (filling) (16) Plug and seal (provisional return) (17) Studs and nuts (18) Pin (19) Stirrup (20) Pin (21) Support (control cable) (22) Screw

Massey Ferguson 6190, 6180 spool valves characteristics

Functions: Double acting; Single and double acting (convertible). These functions are also recognised via the abbreviations SA and DA.

Positions: Three; Four with one in floating position.

Return to neutral: By spring or by an automatic system.

Zero leak: With or without.

Each spool valve is activated by a lever in the cab and it has three phases of travel:

- 35% reduced flow rate;
- 45% progressive increase of flow rate and pressure;
- 20% full flow rate.

The spool valve placed against the flow divider is spool valve No.1. The progressive increase of flow rate and pressure ensures uniform operation of the MF 6180, 6190 implements.

This characteristic also allows two spool valves to be activated simultaneously, the total flow rate being shared. The flow rate to each quick-disconnect coupling is proportional to the position of the control lever.

Operating and adjusting the flow divider

Function of the flow divider

For operations requiring low oil flow rate, the flow divider allows to vary supply to the hydraulic slave device via a knob (4) used to adjust flow rate between “maximum stop” and “minimum stop”.

It is fitted at the inlet of the MF 6190, 6180 tractor auxiliary spool valve assembly. It is supplied by oil from the high flow rate circuit passing through the trailer braking valve or the closing plate (depending on version).

Operation

The oil coming from port (P) is directed to port (X) and supplies the first spool valve. The flow is regulated according to the position of the knob (4). Simultaneously, the pressure in channel (P) allows oil to pass through drilled hole (a) and restrictor (b).

The piston (1) is then moved to the right, allowing oil to be directed towards port (Qx). The intermediate block (7) receives the excess flow rate via the pipe (3).

Adjustment