Note
Fastening of injection timer changed.
1st version
Injection timer is attached to intermediate gear shaft by means of a nut (95) and a ground washer (97).
2nd version
Injection timer is attached to intermediate gear shaft by means of a hex screw (95) M 10 x 45.
3rd version
Models 123.125 (sedan long) and 123.183 (T-sedan) with increased additional load are provided with a
double diaphragm vacuum pump. The double diaphragm vacuum pump is driven via a toothed coupling sleeve, attachment and lubrication are by means of a hollow hex screw (95).
Attention!
Do not mix up the different hex screws and injection timers.
Adjusting range of injection timer changed from 6″ t o 7.5″.
A yellow dot outside on housing serves for identification.
This injection timer i s also installed on engines 617.95 (turbodiesel).
On former engines with filament glow plugs the injection timer (7.5′ adjusting range) may not be installed to prevent damage t o glow plugs.
Removal
1. Remove radiator (20-420).
2. Unscrew suction and pressure line from vacuum pump and remove vacuum pump from cylinder crankcase.
3. Unscrew fastening nut or hex screw of injection timer.
4. Remove cylinder head cover.
5. Unscrew fastening screw for camshaft sprocket (3).
6. Rotate crankshaft in direction of rotation of engine to TDC mark.
Camshaft must be in alignment with marking of compensating washer and 1 s t camshaft bearing (arrow).
7. Mark meshing point of chain on injection timer and position of injection timer in relation to crank-
case with paint.
8. Remove chain tensioner or push back pressure pin (05-31 0).
9. Remove slide rail (4) after removing hex screw.
10. Remove camshaft sprocket, while paying attention to compensating washer between camshaft and
camshaft sprocket. Leave chain on camshaft and place together into chain box.
11. Unscrew lock screw (8) for chain drive and pull out upper bearing pin of slide rail (10) by means of puller.
12. Lift chain from injection timer. For this purpose, slip holder in-between injection timer and chain. For better location, introduce guide pin (arrow) into threaded bore.
13. Remove or push off injection timer.
Attention!
Do not rotate crankshaft and camshaft following removal of injection timer.
14. Remove bushing (2) for injection timer and thrust ring (3) from intermediate gear shaft.
15. Check slide rails (9 and 10) (visual checkup) and replace, if required.
Installation
16. Lubricate thrust ring (3) and bushing (2) and slip on intermediate gear shaft. Pay attention to
correct seat of both Woodruff keys (5) (Fig. item 14).
Note: If an injection timer must be replaced, place used injection timer on new injection timer in such
a manner that the splines of both injection timers are in alignment. Then transfer painted mark on old injection timer on new injection timer.
17. Slip injection timer on intermediate gearshaft.
18. Pull chain in upward direction or lift camshaft sprocket with chain, making sure that the markings
of injection timer and cylinder crankcase are in alignment. If required, rotate injection timer until the markings of injection timer and cylinder crankcase are in alignment. Then pull out holder.
19. Slip camshaft sprocket with chain mounted on camshaft, making sure that the marking of the compensating washer is in alignment with marking of first camshaft bearing.
Check again whether all markings are in alignment, similar to removal and TDC position on balancing disc.
20. Install chain tensioner (05-310).
21. Introduce bearing pins of slide rail (10) into cylinder crankcase (Fig. item 5). Coat bearing pin at end with sealing compound. When knocking-in, make sure that the locking wire of the slide rail engages in notch of bearing pin.
22. Screw in lock screw (8) with new sealing ring and tighten (Fig. item 30).
23. Check begin of delivery and adjust, if required (07.1-1 10 and 115).
24. Vent injection system (07.1-1 40).
25. Mount hex nut and ground washer or hex screw.
Attention!
Use only specified ground washer, part no. 61 5 990 03 40.
26. Check end play of intermediate gear shaft. Should be 0.05-0.12 mm, touch up thrust ring (3), if required.
27. Mount fastening screw for camshaft sprocket and tighten to 80 Nm.
28. Check injection timer for function. For this purpose, turn hex nut or hex screw to the right up to
stop by means of a wrench. Upon release, injection timer should return automatically to i t s old position.
29. Mount vacuum pump with new gasket and connect vacuum lines.
30. Introduce slide rail (4) with holder into bore of outer slide rail (5) and tighten.
31. Mount cylinder head cover, while paying attention to correct seat of rubber gasket.
32. Mount regulating linkage, check and adjust, if required (30-300).
33. Install radiator andconnectall lines.
34. Run engine and check for leaks.