Engine - Will Not Shut OFF When Cold

REF. NO. 07.1/37, 43/6

To: OUR MERCEDES-BENZ PASSENGER CAR DEALERS

DATE: September 1987

SUBJECT:
VACUUM PUMP OIL SUPPLY
ENGINES 602.911, 603.960/.961

As of May 1986 production, the oil supply for the vacuum pump has been modified through the introduction of a second bore in the oil spray nozzle. This will help eliminate customer complaints, such as "the engine will not turn off when cold", which are due to a damaged pump.





Effective Serial Number

In cases of the above mentioned complaint, or when performing repairs that require the removal of the vacuum pump on previously manufactured vehicles, remove the centering sleeve and install a modified gasket to improve the oil supply to the pump.

Procedure

1. Remove fan shroud, fan , and V-belt (see Service Microfiche Engine 601, Mechanical II, job no. 13-340).

2. Remove vacuum pump (see Service Microfiche Brakes, job no. 43-618).





3. Remove centering sleeve, it is no longer to be used (3, Figure 1).

Note:
The centering sleeve must be retained and installed as a guide if removing the fuel injection pump, so that the timing device does not bind when the engine is cranked.





4. Install modified gasket (10, Figure 2)

5. In cases of the aforementioned complaint, install a new vacuum pump.

6. At this time, do not connect the vacuum line for the brake system to the vacuum pump.

7. Reinstall V-belt, fan and fan shroud.

8. With the engine running, pour approximately 50 ccm of engine oil, using an oil can, into the open vacuum line and immediately connect the vacuum line to the vacuum pump.





Parts Information

Time Allowance
Refer to the latest time guide microfiche.