Cagiva Navigator, Руководство по ремонту

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D.97
ENGINE
The valve seating area must be inspected after each cut.
Specific tools: 96768 - Valve seat cutter (N-626)
800096667 - Valve seat working guide
(N-140-5.5)
800096666 - Valve seat working set
• Insert the guide with a slight rotation. Seat the guide snugly. Fit the
45° cutter, the attachment and the T-handle.
• Using the 45° cutter, decoke and clean up the seat with one or two
turns.
• Check the seat using the previously described width measure-
ment procedure. If the seat is pitted or burnt, give it another pass
with the 45° cutter.
To avoid changing the tappet shim, cut the seat as little as possible.
If the seating area is positioned too high on the valve, or if it is too
wide, lower or narrow it by using 15°/60° cutters on the exhaust side
and 30°/60° cutters on the intake side.
If the seating area is too low or too narrow, raise or widen it using the
45° cutter.
• After obtaining the desired valve seat position and width, use the
45° cutter lightly to remove any burrs caused by the previous cut-
ting operations.
DO NOT use lapping compounds after the final cut is made.
The finished valve seat should have a velvety smooth fin-
ish, not a polished and shiny appearance.
This will provide a soft surface for the final seating of the
valve, which will occur during the first few seconds of en-
gine operation.
Seating area too low and too narrow
Seating area too high and too wide.