Removing and Installing Crankshaft Sealing Ring - Flywheel Side
Removing and Installing Crankshaft Sealing Ring - Flywheel Side
Tools
Caution:
When working on the engine, absolute cleanliness is essential. Even the smallest particles of dirt can damage engine components.
A new crankshaft sealing ring is used as of July 2005 (internal designation PTFE ring). This sealing ring can be installed retroactively on all 996 naturally aspirated engines (except for GT3).
- The new sealing ring has the part number 997.101.212.00
- The green support ring is an additional identifying feature.
Note:
- The sealing ring can be replaced on the installed engine in Tiptronic vehicles only up to and including model year 2001.
- To replace the sealing ring in Tiptronic vehicles as of model year 2002, the complete engine/transmission unit must be removed.
- In vehicles with manual transmission, the sealing ring can be changed on the engine, irrespective of whether it is installed or removed.
Note:
- Two new tools are to be used for fitting the crankshaft sealing ring as of August 2002. These replace special tools 9609 and 9609/1.
Tools
Note: The assembly fixture must be converted for fitting the new crankshaft sealing ring (PTFE). The new insert assembly aid 9699/2 -Figure- is fitted into the existing insertion tool 9699.
Removing The Crankshaft Sealing Ring
Note:
- In order to avoid deforming the thrust plate housing, always loosen screws in several stages and in diametrically opposite sequence.
- Make sure not to damage the crankshaft flange when installing and removing the double-mass flywheel or Tiptronic drive plate!
Engine Removed
Remove transmission.
Remove the clutch pressure plate including clutch drive plate. Unscrew 6 M8 x 16 pan-head screws crossways in several stages. Remove the thrust plate, including the drive plate.
- Remove the double-mass flywheel (DMF, manual transmission) or the drive plate for the torque converter (Tiptronic). Unscrew 8 M10 x 1 x 50 pan-head screws for the DMF or M10 x 1 x 25 in the case of the drive plate, remove DMF or drive plate. To counter, fasten toothed segment 9538/1 to the crankcase using an M12 x 50 hexagon-head bolt (fine thread).
Engine installed
- Remove manual transmission.
- Remove Tiptronic transmission up to model year 2001.
1. Remove clutch and flywheel (DMF) or drive plate (Tiptronic).
Note;
- Never use an abrasive or polishing cloth or brushes with metal bristles on the sealing surface of the crankshaft flange!
2. Carefully remove small edges or burrs on the chamfer of the crankshaft flange with an oilstone. Then, carefully degrease the crankshaft journal and crankcase bore (e.g. using a clean, lint-free cloth that has been soaked in solvent naphtha or acetone). Blow dry using a low air pressure (0.5 bar or less) or allow to dry naturally.
Note:
- Clean corroded crankshaft flange.
Clean the crankshaft flange with a special metal-polishing pad (e.g. Nevr Dull , available in car and motor bike accessory stores). Then, carefully degrease the flange (e.g. using a clean, lint-free cloth that has been soaked in solvent naphtha or acetone).
3. Center the old sealing ring on a recess (e.g. round window in the ring) with a drift punch 1-mm tip no. 167.
4. Spot drill the crankshaft sealing ring on the front -arrow- with a 3-mm drill bit, grease the drill bit beforehand.
Note:
- We recommend that you use two alternative tools for removing the crankshaft sealing ring.
5. Screw extractor tip of tool Mod. G puller for sealing rings no.168-1 into the bore and pull out the sealing ring.
Alternatively:
6. Screw sheetmetal screw (5 x 20) with washer approximately 5 mm into the bore.
7. Pull out the sealing ring with the puller 9237 -Arrow-.
8. Clean the crankshaft flange again if necessary using the metal polishing pad. Then, carefully degrease the flange and crankcase bore using a clean, lint-free cloth that has been soaked in solvent naphtha or acetone. Allow this to dry for at least three minutes so that the acetone vapours do not damage the new sealing ring.
9. Check crankshaft flange and housing bore for damage.
Installing The Crankshaft Sealing Ring
Note;
- The tools should be thoroughly examined for any burred spots each time a sealing ring is fitted. Even minor damage to the tool can damage the micro sealing lips of the new sealing ring!
1. Small burred spots or damaged areas on the tools can be eliminated with a nail file, then pull off with a fine abrasive or polishing cloth. Remove residual dirt on the tools, e.g. using solvent naphtha or acetone.
2. Check crankshaft installation position. To do this, insert special tool measuring mandrel 9699/1 across the crankshaft flange into the fitting bore of the crankcase -Figure-.. The measuring mandrel must be placed with slight resistance in the bore. If the measuring mandrel cannot be positioned, the engine must be replaced.
Caution:
Damage to the sealing lip.
- The crankshaft flange and tools must be clean and free of grease.
- The sealing ring must be fitted dry - with no oil, grease or other lubricants.
- The crankcase bore must not be oiled.
- The sealing ring must only be positioned on the assembly tool with the support sleeve.
- The new crankshaft sealing ring (PTFE) is supplied as a spare part on a green support sleeve.
- Do not remove the sealing ring from the support sleeve.
Result: Leaks.
3. Adjust the insertion tool for positioning the sealing ring support sleeve. Only unscrew the hexagon-head bolt until the groove of the assembly aid is flush with the contact surface of the sleeve -Arrow-.
4. Slide the new crankshaft sealing ring -Item 1- with the green support sleeve -Item 2- onto the assembly aid 9699/2 by pressing only on the sleeve. The collar of the sleeve must be pointing away from the tool -Inset- . Make sure the sealing ring is dry before fitting it.
5. Fit insertion tool 9699 between the two internal M8 pan-head screws, (hexagon socket a/f 8) -with hexagon socket-wrench insert- on the crankshaft flange and secure it. The crankshaft flange's dowel pin must sit in the bore of the tool.
6. To position the crankshaft sealing ring correctly on the crankshaft flange, turn an open-end/ring wrench in a clockwise direction as far as it will go on the hexagon (a/f 19) of the tool. Leave the tool in place for approximately one minute.
7. Remove the tool. Loosen the large hexagon-head bolt and the two hexagon socket head bolts alternately on the crankshaft flange until the tool can be removed.
8. Check that the sealing ring is properly seated and aligned. To do this, measure the distance from the flywheel contact surface on the crankshaft flange to the sealing ring (outer radius) at four points offset by 90°.
Installation dimension of crankshaft sealing ring from flywheel contact surface to sealing ring: 13 mm
9. Leave support sleeve on the tool following installation to protect the edges of the tool. To remove the sleeve, carefully lever it off at the bore with a small screwdriver -Arrow-.
10. Install the DMF or drive plate. Make sure that the crankshaft flange is not damaged.
11. Install the clutch pressure plate and drive plate.
12. Refit or install the transmission.
13. Install the engine/transmission unit if necessary.