Examination
1. Check that the throttle cable is adjusted correctly (see Chapter 4B).
2. Start the engine and warm it up to normal operating temperature. With the parking brake applied and the transmission in neutral, let the engine idle. Make sure that all electrical consumers in the car are turned off (including air conditioning, where fitted).
3. Using a diesel engine tachometer, check that the idle speed is correct Technical Data. If adjustment is necessary, follow the steps in the next section.
Adjustment
Engines with pneumatic idle increase
4. Loosen the jam nut on top of the idle speed vacuum assembly that mounts on the back of the injection pump (see fig. 9.4).
Pic. 9.4. Loosen locknut (A) and turn the vacuum assembly (IN), to adjust idle speed. - engines with a pneumatic increase in speed x.x.
5. Using an open-end wrench, gradually turn the vacuum assembly until the xx speed is within specifications. After completing the adjustment, tighten the locknut.
Motors with electromagnetic control (ELR) idle speed
6. Disconnect the plug from the electromagnetic relay, which is installed on the back of the injection pump (see fig. 9.6).
Pic. 9.6. Remove the plug (shown by arrow) electromagnetic relay - engines with ELR speed control x.x.
7. Locate the idle speed adjustment screw. which is located immediately above the body of the electromagnetic relay (see fig. 9.7). Loosen the lock nut and turn the adjustment screw to set the normal idle speed. Remember: Turning the screw to the left increases and turning to the right decreases the RPM xx
Pic. 9.7. Speed adjustment screw x.x. (shown by arrow) - engines with ELR speed control x.x.
8. After completing the adjustment, tighten the locknut and connect the plug.
Engines with EDS idle speed control
9. Follow the steps described in p.p. 6-8, inclusive. Please note that the basic speed setting x.x. can be changed electronically using a compensating socket.