Valves - MTD P90 series Shop Manual

Valves

The valves and valve seats can be serviced by grinding and lapping or the head can be replaced. Depending on
local machine and labor costs, it is probably more economical to replace the cylinder head versus servicing the
valves.
Valve adjusters
Figure 9.9
Figure 9.10
Valve keeper
To service the valves:
NOTE: Servicing valves during the warranty period will
void the warranty. Warranty valve repairs are to be
accomplished by replacing the cylinder head.
1. Remove the cylinder head by following the steps
described earlier in this chapter.
2. Remove the rocker arms by:
2a. Remove the jam nuts.
2b. Remove the fulcrum nut.
2c. Slide the rocker arms off of the rocker studs.
3. Remove the valve adjusters. See Figure 9.9.
NOTE: It may be necessary to press down on the valve
retainers to unseat the adjusters.
4. Remove the valve retainers by applying light finger
pressure and moving the retainer so that the valve
stem passes through the large part of the "keyhole"
opening in the retainer. See Figure 9.10.
NOTE: The valve keepers are not interchangeable.
NOTE: If the engine has a dropped valve, remove the cyl-
inder head, inspect the valve and the piston for
damage.
Cylinder head
87