B1BT08K1 - 206 DW8 ENGINE
MODIFICATION DW8 ENGINE
The removal/refitting of these new units does not present any particular difficulty .
The cylinder head cover sealing function has changed and must be carried out with care .
1 - DRIVING THE ANCILLARIES
The ancillaries pulley (1) is made of stamped metal with integrated vibration damper .
This pulley differs in the shape of the exterior crown wheel .
There is complete interchangeability between a part of the previous design and a new part .
2 - SEALING OF BEARING NO. 1
The appearance of the seal has not changed, only the material is different .
There is complete interchangeability between a part of the previous design and a new part .
3 - CYLINDER HEAD
3 - 1 - CYLINDER HEAD GASKET
Addition of a cylinder head gasket to accommodate better the range of piston protrusion .
IMPERATIVE : select the cylinder head gasket in relation to the protrusion of the pistons .
(A) Engine identification .
(B) Thickness identification .
| DW8 engine | |||
|---|---|---|---|
| piston protrusion (*) | gasket thickness compressed | number of holes at A | number of holes at B |
| 0.51 to 0.55 mm | 1.26 ± 0.04 mm | 2 | 1 |
| 0.55 to 0.59 mm | 1.30 ± 0.04 mm | 2 | 2 |
| 0.59 to 0.63 mm | 1.34 ± 0.04 mm | 2 | 3 |
| 0.63 to 0.67 mm | 1.38 ± 0.04 mm | 2 | 4 |
| 0.67 to 0.71 mm | 1.42 ± 0.04 mm | 2 | 5 |
| 0.71 to 0.79 mm | 1.46 ± 0.04 mm | 2 | 3 |
| (*) : use the highest piston as a reference | |||
3 - 2 - SEALING OF THE CYLINDER HEAD COVER
The cylinder head assembly consists of 3 components :
These 3 components are now sealed by type E7 sealing compound .
The cylinder head covers (2) and (3) no longer have a recess for a pre-formed gasket .
4 - REMOVAL
DW8 ENGINE
REMOVE THE CYLINDER HEAD ASSEMBLY .
NOTE : the use of sealing compound may make separation of the components difficult .
WARNING : clean the joint faces with an approved descaling product ; do not use abrasives or sharp tools on the joint faces ; the joint faces must not have any trace of knocks or scores .
The dry sealing compound can be removed easily from the flat surfaces of the casings .
However, for precise cleaning, use a wooden or plastic spatula .
5 - REFITTING
DW8 ENGINE
Apply sealing compound (a) in an even bead of approximately E7 mm diameter round the edge of the cylinder head cover 3.5 .
Refit the lower cylinder head cover on the cylinder head .
Once the components are in contact, engage the mounting bolts and tighten them to a torque of 0.5 ± 0.1 dan.m starting with the centre bolt .
Apply sealing compound (a) in an even bead of approximately E7 mm diameter round the edge of the cylinder head cover 3.5 .
Refit the plastic cylinder head cover .
Engage the mounting bolts .
Pre-tighten the bolts to 0.8 ± 0.1 m.daN ; Angular tightening 50° (+0° ; +5°) .
IMPERATIVE : proceed bolt by bolt in the order shown .
WARNING : to prevent damage to the sealing compound on refitting, avoid any movement of the components while bolting the assembly .
NOTE : the plastic cylinder head cover mounting bolts are self-cutting. refitting them in the holes already cut does not present any difficulties but it is recommended that the bolts are engaged as straight and as deeply as possible ; clean the bolts before refitting .
6 - CYLINDER HEAD BOLT
The cylinder head bolts are male torx recess bolts with captive washer .
IMPERATIVE : before reusing the cylinder head bolts, check their length .
X = Maximum length below head .
Length of reusable bolts X = 125.5 mm .
IMPERATIVE : do not re-use cylinder head bolts if they are longer than 125.5 mm .
NOTE : pass a tap M12 X 150 into the internal screw threads of the cylinder block receiving the cylinder head bolts .
Fit the cylinder head bolts coated with MOLYKOTE G RAPID PLUS on the threads and under the bolt heads .
IMPERATIVE : do not lubricate the new bolts .
DW8 ENGINE
Tightening procedure :
There is complete interchangeability between a part of the previous design and a new part .
Combining the bolts is permitted .
6 - 1 - VALVE STEM SEALS
Valve stem seals : Brown .
There is complete interchangeability between a part of the previous design and a new part .
6 - 2 - VALVE SPRINGS
The valve springs are painted yellow to enable them to be identified .
There is complete interchangeability between a part of the previous design and a new part .
7 - TIMING BELT TENSIONER ROLLER
Tensioner roller with steel pulley .
There is complete interchangeability between a part of the previous design and a new part .
8 - LUBRICATION
The moulded body of the piston head coolers has changed to a mechanical welded tube body .
There is complete interchangeability between a part of the previous design and a new part .
9 - COOLING SYSTEM
The coolant pump turbine is made of brown plastic .
The new turbine/coolant pump pinion assembly is interchangeable with the previous design .