Operation CHARM: Car repair manuals for everyone.

B. M/RSF-Injection Pump With Mechanical Governor

Operation of Injection Pump and RPM Governor

B. M/RSF-injection pump with mechanical governor

Layout of M/RSF-injection pump corresponds essentially to that of M-injection pump.

Lubrication of injection pump




The injection pump is connected to engine oil circuit via intermediate gear shaft (refer to group 05) and via injection pump-camshaft (1) which is provided with an oil bore.

The return oil flows via ring gap on bearing cap (2) back into cylinder crankcase.

The drive pinion is provided with an 0-ring (3) to seal the clutch space between intermediate gear shaft and camshaft.

Relief choke in pipe connection




Relief chokes are installed in pipe connections of injection pump to reduce hydrocarbons in exhaust gas. A ring groove on pipe connection (arrow) serves for identification. The relief choke (2) is a plate valve (3) which opens in direction of injection nozzle and is provided with an orifice of 0.6 mm dia. The valve seat (4) is riveted into pipe connection.

Layout and operation of RSF-governor







The governor is an idle speed-max. speed governor with its control spring (16) dimensioned and adjusted in such a manner that the governor is not governing in partial load range, except for adaptation (refer to "control during start and full load").

In partial load and full load range, the control rod (22) of the injection pump is operated by means of accelerator pedal only, which is connected to the adjusting lever (10) of governor via regulating linkage.

The adjusting screw (3) pre-loads idle speed spring and adjusts the idle speed.

Regulation during start and full load




If, with the engine stopped, the adjusting lever (101 is placed against full load stop (fixed stop on governor housing) the reverse transfer lever (6) will rotate around pivot "B" and will take the regulating lever (7) along in direction of start.

In full load position of adjusting lever (10) ("full throttle") the idle speed auxiliary spring (18, poppet) is pushed away from guide lever by the idle speed auxiliary spring-shutoff (13). As a result, speed regulation from starting position of governor will be faster.

After passing through idle speed stage (c) the governor sleeve (11) rests against spring capsule (8). This will move control rod of injection pump into full load position via reverse transfer lever (6) and regulating lever (7).

After attaining a given speed, the influence of the spring capsule (8) is overcome by a given distance (d) (adaptation).

If the engine speed is still further increasing, the force of the fly weights is enough to overcome regulating spring (16) (full-load speed regulation).

Break away depends on preload of regulating spring (16).

Regulation at idle




Linkage lever (19) rests against idle speed stop screw (5). AT increasing speed the governor sleeve (11) runs through idle speed stage. Guide lever (4) swivels around pivot "A" and thereby acts against idle speed spring (17).

At a given speed the guide lever (4) rests against adjusting nut of idle speed auxiliary spring (18). The movement of the governor sleeve (11) is transferred to control rod of injection pump via reverse transfer lever (6) and regulating lever (7) in similar direction. After running through idle speed stage, the governor sleeve (11) will rest against spring capsule (8).

If the engine speed continues to increase, (e.g., under deceleration) the spring capsule (8), at a given speed, and then the regulating spring (16) will be overcome. This will move control rod into "stop position".

Stop position of governor




The vacuum control unit (1) is provided with vacuum from vacuum pump via steering lock of the vehicle. As a result, the diaphragm of the vacuum control unit is attracted against pressure of compression spring.

The vacuum control unit (1) is connected to a stop lever (20). This lever will swivel around pivot "D" and will thereby pull the control rod of the injection pump into "stop position", while the shunt spring of the regulating lever will be overcome. The emergency stop lever (21) can be applied to pull the control rod likewise from outer side of governor into "stop position".