Check that the camshafts (marked "VA" and "VS" for the vertical head and "OS" and "OA" for the horizontal head) are clean
and in good condition.
If the camshafts are not new, use emery cloth to remove signs of wear on the cam and support surfaces, working on a flat surface.
Use specified lubricant (Molycote M55 Plus) both on the cylinder head and on supports (10) and (11), to lubricate the seats
of the camshafts (see green areas).
Fill tanks (A) with specified lubricant (Molycote M55 Plus).
Apply sealant (Three Bond 1215 sealing compound) at the four points (highlighted in red) of the support surface (11) shown
in red in the figure.
Clean off any excess of sealant.
Apply sealant only on the timing side support (11) and not on support (10).
Install the camshafts (16) and (17) in the cylinder head, and rotate them to distribute the lubricant evenly.
Check that the centring dowels (12) are present.
Pre-tighten screws (8) and special screws of caps (10) and (11) to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm).

Note
Pre-tighten one cap at a time in the sequence indicated in the figure.
Then tighten screws (8) to a torque of 22.5 Nm (Min. 21 Nm - Max. 25 Nm).

Note
Tighten one cap at a time in the sequence indicated in the figure.
Remove any excess of sealant from between the cylinder head and the cap (11).
Turn the camshafts (16) and (17) by hand to check that they rotate freely.

Note
The first screw to be tightened must the one indicated in the figure (intake and timing side).

Important
Now, proceed checking the valve clearance.
Before installing seal rings (15) make sure that the relevant seats (B) on the head are perfectly clean.
Remove any excess of previously applied lubricant.
Lubricate seats (B) with KLÜBERPLUS S 06/100 (or denatured alcohol).
Only in case the ring has not been previously lubricated, lubricate the internal diameter of seal rings (15) with Shell Retinax
LX2 grease (or alike), or lubricate the cap external diameter with engine oil (better if wrapping the cap in a cloth soaked
in engine oil).

Note
Always make sure that the cap, the seal rings and their seats are free from surface flaws (dents, scratches, etc.) and dirt
(dust, other solid residues).
Fit seal rings on camshafts (16) and (17) using tool (Z)
88713.2861.

Note
Once installed, the seal rings must be positioned as indicated. Clean any excess of lubricant with a clean cloth.

Note
Some figures below show magnesium head cover, but the model described in the manual is equipped with aluminium alloy covers.
Apply sealant (Three Bond 1215 sealing compound) at the four points (C) highlighted in red of the cylinder head cover (5)
as shown.
Fit the gaskets (6) and (7) on the cylinder head cover (5), as shown in the figure.
Cylinder head cover identification: the vertical head cover (5) has a tooth (A) on the left-hand side (exhaust side), whereas cover
(9) has a tooth (B) on the right-hand side (exhaust side).
Apply a bead (F) of 2 mm (max. 4 mm) of sealant (Three Bond 1215 sealing compound) on the four areas (D) of head surface (E)
(approximately in the middle of the cap machined surface, as indicated), by respecting the values and position (G), i.e. 10
÷ 11 mm from the cap edge.
Value (M) is approximately 19 mm.
Fit cover (5) with pre-fitted gasket on the head, as shown.
Centre the cover in the four fixing holes.
Fit O-rings (4) on screws (3).
Tighten the screws (3) to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm), respecting the indicated sequence.
Thoroughly remove any excess of previously applied sealant between cylinder head and cover.
Valve clearance specified values: