John Deere 6068 Lawn Mower User Manual


 
Lubrication & Maint./2000 Hour/24 Month
DPSG,RG41165,137 –19–27JUL06–2/5
4. With engine lock-pinned at TDC of No. 1 piston’s
compression stroke, check valve clearance to following
specifications. (Use sequence for 4-cylinder or
6-cylinder engines as outlined on next page.)
Specification
Intake Valve Clearance For
Checking (Rocker Arm-to-Valve
Tip) (Engine Cold)—Clearance 0.31—0.38 mm
(0.012—0.015 in.)
.........................................
Exhaust Valve Clearance For
Checking (Rocker Arm-to-Valve
Tip) (Engine Cold)—Clearance 0.41—0.48 mm
(0.016—0.019 in.)
.........................................
DPSG,RG41165,137 –19–27JUL06–3/5
RG7409 –UN–06AUG96
Adjusting Valves
A—Adjusting Screw Jam Nut
5. If valves need adjusting, use the appropriate valve
clearance adjustment procedure on the next page and
adjust to specifications below. Loosen the jam nut (A)
on rocker arm adjusting screw. Turn adjusting screw
until feeler gauge slips with a slight drag. Hold the
adjusting screw from turning with screwdriver and
tighten jam nut to specifications. Recheck clearance
again after tightening jam nut. Readjust clearance as
necessary.
Specification
Intake Valve Clearance For
Adjusting (Rocker Arm-to-Valve
Tip) (Engine Cold)—Clearance 0.36 mm (0.014 in.)..................................
Exhaust Valve Clearance For
Adjusting (Rocker Arm-to-Valve
Tip) (Engine Cold)—Clearance 0.46 mm (0.018 in.)..................................
Rocker Arm Adjusting Screw Jam
Nut—Torque 27 N•m (20 lb-ft)....................................................................
6. Replace rocker arm cover and crankcase ventilator
tube.
Continued on next page
35-10
080706
PN=168