Front Crankshaft Seal: Service and Repair
WM 137419 Removing and installing crankshaft sealing ring - belt side
Tools
Technical values
Preliminary work
WARNING
Objects or loads falling down
- Risk of squashing or crushing
-> Secure components to prevent them from falling down.
1. Lower the engine.
-> 1001IN Lower the engine to complete other work 1001IN Lower the engine to complete other work.
2. Remove engine carrier.
-> 103019 Removing and installing engine carrier 103019 Removing and installing engine carrier.
3. Remove vibration damper.
-> 137519 Removing and installing vibration damper Service and Repair.
Removing crankshaft sealing ring - belt side
CAUTION
The crankshaft flange can be damaged if not cleaned correctly.
- Leaks
-> Never use an abrasive or polishing cloth or brushes with metal bristles.
-> Follow cleaning instructions.
WARNING
Caustic fluids
- Danger of chemical burns
-> Avoid contact with caustic fluid.
-> Wear personal protective gear.
-> Ensure that there is good ventilation.
-> If you do come into contact, wash off immediately with plenty of warm water and contact a doctor if necessary.
Information
- Work on delicate engine parts must be carried out conscientiously and precisely.
- Use a suitable tray.
- Absolute cleanliness is essential.
Crankshaft sealing ring -1- on crankshaft flange with bore positions -arrows-.
Bore positions for sealing ring
1. Prick-punch the crankshaft sealing ring with a mandrel -1- ( -arrow- ).
Prick-punching sealing ring
NOTICE
Drilling crankshaft sealing ring.
- Risk of engine damage caused by drilling chips.
- Risk of damage to the crankcase.
- Do not apply pressure while drilling.
-> Carefully remove chips.
-> Drill carefully.
2. Drill holes in the crankshaft sealing ring -1- at two directly opposite positions -arrows- using a greased drill bit (dia. 2 mm) and carefully remove drill chips.
2.1. A battery-powered screwdriver -2- or a small power drill can be used for drilling holes.
Drilling holes in sealing ring
3. Pull out sealing ring.
3.1. Screw two tapping screws (4 x 20, for example) with washers -1- into the bore holes.
Screwing in tapping screws
3.2. Pull sealing ring out alternately using slide hammer kit Nr.168 -2 and 3- at the tapping screws -1-.
Pulling out sealing ring
Information
Visually inspect the crankshaft flange and crankcase bore for damage.
4. Check crankshaft flange and crankcase bore for damage.
4.1. Remove traces of corrosion on the flange with a metal-polishing pad (Nevr Dull has been approved, available in car and motor bike accessory stores).
4.2. Then carefully wipe off the flange using a clean, lint-free cloth that has been soaked in solvent naphtha or acetone.
4.3. Leave to dry off for at least three minutes to ensure that the vapours of the cleaning agent do not attack the new sealing ring (sealing lip).
Installing crankshaft sealing ring - belt side
NOTICE
Incorrect tool
- Risk of damage to components
-> Use prescribed tool.
Tool overview:
Tool and sealing ring
WARNING
Caustic fluids
- Danger of chemical burns
-> Avoid contact with caustic fluid.
-> Wear personal protective gear.
-> Ensure that there is good ventilation.
-> If you do come into contact, wash off immediately with plenty of warm water and contact a doctor if necessary.
1. Small burred spots or damaged areas on the tools can be filed down with a nail file, then removed with an oilstone or fine abrasive or polishing cloth.
1.1. Remove residual dirt on the tools using solvent naphtha or acetone.
CAUTION
Damage to the sealing lip.
- Leaks
-> The crankshaft flange and tools must be perfectly clean and free of grease.
-> The sealing ring must be fitted dry, i.e. no oil, grease or other lubricants can be used.
-> The crankcase bore must not be oiled.
-> The sealing ring can only be positioned on the assembly tool using the supporting sleeve.
-> The new crankshaft sealing ring (PTFE) is supplied on a supporting sleeve as a spare part.
-> Do not remove the sealing ring from the supporting sleeve.
2. Position the crankshaft sealing ring -2- and support ring -3- dry on the insertion part -1-. Apply pressure only to the support ring when doing this.
2.1. Do not use lubricants.
Sealing ring on insertion part
3. Fit the crankshaft sealing ring -1- and insertion part -2- on the crankshaft flange.
3.1. Tighten the tool hand-tight on the crankshaft flange using the two M8 cheese head bolts (hexagon socket, a/f 8) -3-.
Positioning sealing ring with insertion part
4. Assembly aid 9774 -1- must now be fitted on the insertion part with the crankshaft sealing ring -2-.
4.1. To do this, place the hexagon-head bolt for the assembly sleeve onto the thread of the insertion part.
Fitting assembly sleeve
5. Insert the crankshaft sealing ring.
5.1. Assembly aid 9774 -2- must now be screwed in slowly clockwise as far as it will go using a ratchet -1-.
5.2. Leave the tool fitted for two minutes to allow the sealing lip to settle into position.
Inserting sealing ring using tool 9774
6. Remove assembly aid.
6.1. Undo the hexagon-head bolt and take off the assembly sleeve.
6.2. Unscrew two cheese head bolts on the insertion part and remove the component and support ring.
6.3. Leave the support ring in position after fitting it on the tool to protect the edges of the tool.
7. Use a caliper gauge to check that the crankshaft sealing ring is seated correctly and is straight.
7.1. To check this, take measurements at four different places, offset by 90°, from the crankshaft flange surface to the crankshaft sealing ring (level surface).
=> Measured value: 2.7 mm+/-0.3 mm
Subsequent work
1. Install vibration damper.
-> 137519 Removing and installing vibration damper Service and Repair.
2. Install engine carrier.
-> 103019 Removing and installing engine carrier 103019 Removing and installing engine carrier.
3. Place engine in installation position again and secure it.
-> 1001IN Lower the engine to complete other work 1001IN Lower the engine to complete other work.
-> 100119 Removing and installing engine 100119 Removing and installing engine.