Crankshaft Mechanism Reassembly

SPECIAL TOOLS
- Standard Handle tool No. 999 1801, or equivalent
- Assembly tool No. 999 5430, or equivalent
- Guide Pins tool No. 999 5502, or equivalent
- Magnetic Plate tool No. 999 5971, or equivalent
- Magnitic Stand tool No. 999 9696, or equivalent

UNIVERSAL TOOLS
- Piston Ring Compressor tool No. 115 8281, or equivalent
- Short Haired Roller tool No. 951 1205, or equivalent
- Piston Ring Pliers tool No. 998 5424, or equivalent

PROCEDURE





1. Classification of crankshaft main bearings
- Clean main bearing seats.
- Check that components are clean and undamaged.
- Check classification on cylinder block and crankshaft.

Each main bearing seat is marked with the cylinder number and a classification letter for the block and crankshaft. Use the table below to select the correct bearing.





2. Selecting bearing
- Install main bearing in cylinder block as in table.
- Oil bearing shells liberally on crankshaft side.
- Install flanged shells in rearmost position.

Example: Classifying No. 1 bearing.

Marking on block is B
Marking on crankshaft is C
Install a Red bearing in the block and a Yellow bearing in the intermediate section.





3. Intermediate section
- Apply liquid sealing compound part No. 1 161 059-9, or equivalent, to intermediate section.
- Cover entire surface, but do not allow to overflow, as this may block ducts and bolt holes.
- Use short-haired roller tool No. 951 1205, or equivalent.
- Place bearing shells in intermediate section.
- Make sure bearing shells are dry between bearing and block. Otherwise bearing may rotate along with crankshaft.
- Oil bearing shells and flange bearing (furthest back)





4. Install crankshaft
- Install crankshaft. Do not turn crankshaft before intermediate section has been tightened.
- Put intermediate section in position.
- Tighten intermediate section/crankshaft bolts in five stages in numerical order as shown in the image.
- Each stage must be complete before starting the next.

Stage 1 - Tighten all 10 mm bolts to: 20 Nm (15 ft. lbs.)
(skip all 7 mm and 8 mm until stages 3 and 4.)

Stage 2 - Tighten 10 mm bolts to: 45 Nm (33 ft. lbs.)

Stage 3 - Tighten 8 mm bolts to: 24 Nm (18 ft. lbs.)

Stage 4 - Tighten 7 mm bolts to: 17 Nm (13 ft. lbs.)

Stage 5 - Finally, tighten 10 mm bolts to: 90°

Max. length of 10 mm bolts: 118.00 mm





5. Measure crankshaft end play
- Check that crankshaft turns smoothly.
- Measure end play.
- Use dial gauge, magnetic plate tool No. 999 5971 and magnetic stand tool No. 999 9696, or equivalents.

Crankshaft end play: 0.08-0.19 mm





6. Install crankshaft rear seal
- Use standard handle tool No. 999 1801 and assembly tool No. 999 5430, or equivalents.
- Oil mating surfaces between seating flange and seal and between seal lips. Place seal on drift.
- If there are wear marks on crankshaft' push seal further in than before by removing a spacer from the tool.
- Tap seal in until drift meets crankshaft.





7. Assemble pistons and connecting rods
- Insert circlip and check that ring springs apart and locks in groove.
- Circlip opening should point downwards.
- Arrow on piston crown must point forwards, (towards timing belt end of engine).
- Number markings on conrods must face towards intake side of block (starter motor side).

Piston Replacement Notes:
- Later B6304 engines have two types of pistons, which differ in terms of their upper compression rings.
- Version 1 can be replaced by version 2 without having to replace all pistons.
- Version 2 must not be replaced by version 1.

Connecting Rod Replacement Notes:
- Conrods are symmetrical and can be used either way round.

Connecting Rod Marking:
- Install conrod, then tighten bolts to 20 Nm (15 ft. lbs.) and check that bearing cap is pointing in the right direction.
- Put big end in a vice with copper inserts or similar.
- Mark both halves with the cylinder number using a number punch or die.





8. Install piston rings
- Use piston ring pliers tool No. 998 5424, or equivalent.
- Turn piston rings so gaps are approx. 120° apart.

A = Upper compression ring: Text facing upwards
B = Lower compression ring: Groove facing downwards
C = Oil scraper ring: Text facing upwards.

- Clean and dry bearing seats in conrods and caps.
- Install bearing shells in conrods and caps.
- Install guide pins tool No. 999 5502, or equivalent.

NOTE: If reusing original bearing shells, components must be located in original positions.





9. Install pistons in bores
- Use piston ring compressor tool No. 115 8281, or equivalent.
- Oil cylinder bores, pistons and bearing shells.
- When fitting each piston, turn crankshaft so crank pin is at its lowest position to fit the piston in.
- Check that piston classification is correct.
- Tap piston down into bore with hammer shaft.

NOTE: Arrows on piston crown must point towards front, i.e. timing belt, end of engine.





10. Install bearing caps
- Remove guide pins and install caps.
- Do not turn crankshaft until conrod bearing caps have been tightened.
- Check that conrod and bearing cap markings match.
- Use new bolts.
- Oil bolts, and tighten in two stages:

Stage 1 - Tighten to 20 Nm (15 ft. lbs.)
Stage 2 - Tighten an additional 90°

- Check that conrods are free to move laterally.





11. Install oil pump suction pipe
- Put gasket on pipe.
- Reconnect pipe.
- Tighten to 17 Nm (13 ft. lbs.).
- Install new oil passage seals.





12. Install oil pan
- Apply liquid sealing compound part No. 1 161 059-9, or equivalent to pan.
- Use short-haired roller tool No. 951 1205, or equivalent.
- Insert four bolts and align pan flush with rear face of block.
- Permitted alignment tolerance is ± 0.025 mm.
- Tighten bolts back and front to 17 Nm (13 ft. lbs.).
- Install new oil filter.