Part 1
Disassembling and assembling crankcase - GT3
Tools
Note;
- Two additional threaded holes must be made before the special tool is screwed together with engine holder P 201 for the first time.
Adapting engine support
Note;
- The threaded holes are necessary only when the adapter ring is used for the first time
1. Centre adapter on engine support: Fasten adapter half with the existing holes -arrows- on the engine support with two M10 x 60 auxiliary screws. Use a � 6.5 drill bit to spot-drill or countersink the engine support through the holes in the adapter ring. The adapter ring serves as the drilling template.
2. Rework engine support: Drill a core hole for a M6 thread at the spot-drilled points. Drill the holes using a � 3mm drill bit, then with a � 5mm drill bit.
3. Drill core hole and cut the thread.
4. Fasten adapter on engine support: Fasten the adapter on the engine support using the included hexagon socket pan-head screws (M6 x 35).
5. Fit engine support with adapter half: Fasten engine support with attached adapter half onto the crankcase half of cylinder bank 4 - 6.
6. Fasten the second adapter half on the crankcase: Screw the screw sleeves onto the studs and tighten by hand. Fit the connecting screws of the adapter halves and tighten to 10 Nm (7.5 ft. lbs.). Then tighten the installation sleeves.
Left crankcase half (cylinder bank 1 - 3)
Right crankcase half (cylinder bank 4 - 6)
Disassembling the crankcase
Note;
- The thrust plate, driving plate and flywheel must be removed before the engine is fastened to the engine support or assembly support.
1. Position toothed segment (special tool P210b) on the stud and undo the pan-head screws of the clutch thrust plate in several stages and in diametrically opposite sequence, in order to avoid deforming the thrust plate.
2. Fasten assembly fixture P238b with holder P140 onto the stud. Undo the flywheel screws and remove the flywheel. Make sure that the pulse generator is not damaged.
3. Loosen belt pulley. For this purpose, a second person should counter with holding wrench 9548 at the same time. Do not use the hexagon-head bolt again.
4. Force vibration damper (belt pulley) off with the forcing screw 9285/1.
5. Unscrew the 18 hexagon nuts (M8) from the housing bolts.
6. Undo the hexagon nuts (a/f 17) of the left crankcase half (cylinder bank 1 - 3).
7. Loosen tension rod bolts from the outside to the inside.
Note;
- The tension rod bolts of bearing supports 2, 3, 4 and 5 -arrows- can be removed only after removing the crankcase half (cylinder bank 1 - 3).
Removing tension rod bolts
8. Remove crankcase half (cylinder bank 1 - 3).
9. Remove O-rings and tension rod bolts of bearing supports 2, 3, 4 and 5.
Assembling the crankcase
1. Fasten engine support P201 on the right crankcase half (cylinder bank 4 - 6).
2. Check the matching number of the crankcase halves. The number is at the top on the lug.
Note;
- The tolerance groups are 0 and 1
3. Allocate the crankshaft gearwheel and the intermediate shaft to the crankcase. The tolerance group number is stamped on the crankcase -arrow and must be identical to that of the intermediate shaft gearwheel and crankshaft gearwheel.
Matching number on the crankcase
Matching number on the crankshaft gearwheel -arrow-
Matching number on the intermediate shaft gearwheel -arrow-
4. Clean crankcase halves thoroughly. Examine the take-up bores of the tension rod bolts for foreign objects (e.g. seal remnants).
5. Fit intermediate-shaft bearings. Place new bearing shell halves into the crankcase half of cylinder bank 4 - 6.
6. Oil the bearing surfaces. Insert intermediate shaft and check for true running.
7. Insert new crankshaft bearing shell halves into the crankcase. Oil the bearing surfaces.
8. Check whether the dowel sleeves are present and seated properly.
9. Place crankshaft (without bearing 8) into the crankcase half of cylinder bank 4 - 6.
Note;
- If the wear dimension has been reached, the intermediate shaft and the matched drive gearwheel must be replaced.
10. Check circumferential backlash of the intermediate shaft. Fasten a dial-gauge holder, e.g. VW 387, onto the crankcase joint surface for this purpose. The sealing surface must not be damaged when this is done. Align the dial gauge on a tooth face and measure the backlash. Then turn the intermediate shaft by 180° and repeat the measurement.
Circumferential backlash:
New dimension: 0.035 - 0.084 mm
Wear dimension: 0.10 mm
11. Remove intermediate shaft again.
12. Have a second person lift the crankshaft slightly, and slide bearing No. 8 onto the crankshaft journal.
13. Lower the crankshaft slowly and insert crankshaft bearing No. 8 into the locating pin.