Injection Timing With Low Pressure Flow Method

Fig. 43 Injection Pump Timing Check Overflow Pipe:

CAUTION: ONLY ROTATE ENGINE BY HAND DURING THIS PROCEDURE

1. Thoroughly clean around the injection pump discharge area. Disconnect the vacuum line from the vacuum shut off unit.
2. Disconnect the injection line from the #1 discharge port on the injection pump.
3. Remove the delivery valve holder, compression spring, and delivery valve from the #1 discharge port on the injection pump.

CAUTION: DO NOT UNSCREW THE FLANGE BUSHING AS THIS WILL REQUIRE AN ADJUSTMENT AT A BOSCH SERVICE CENTER.

NOTE: In order to properly check injection pump timing, the copper sealing ring and the delivery valve body body must be installed to prevent fuel from flowing continuously when pump is set to the proper timing position.
4. Install the delivery valve holder and overflow pipe, Fig. 43.
5. Rotate the crankshaft in the direction of engine rotation to the point just prior to the start of delivery on the compression stroke of the #1 cylinder.
6. Open the vent on the fuel filter and fill with a hand pump so that fuel flows out of the overflow tube.
7. Move the control lever on the injection pump to the full throttle stop and hold there during testing.
8. Turn the crankshaft in the direction of engine rotation until the fuel stream out of the overflow tube slows to one drop a second.
9. Read the setting of the injection pump timing from the timing marks on the vibration dampener. If the reading is 24° ±1°, proceed with step 10. If the reading does not meet the specifications, adjust the fuel injection pump timing by positioning the engine at 24° BTDC, loosening the injection pump, and rotating injection pump until the stream exiting the overflow tube slows to a drop a second. Tighten the injection pump mounting bolts.
10. Remove the delivery valve holder and overflow tube.
11. Remove the delivery valve body and check for freedom of movement of the delivery valve in the delivery valve body.
12. Install the delivery valve with the groove on the bottom and install the delivery valve and compression spring.
13. Lubricate the threads of the delivery valve holder, install and tighten delivery valve holder to 30 - 37 ft. lb. (40 - 50 Nm).