Craftsman 580.327141 - Manual (Page 14)

Retorque Head Bolts
After the first 50 hours of operation, you must retorque
the head bolts to 4.0 kg.-m. (22 ft.-lbs.)
IMPORTANT: If you feel uncomfortable about doing
this procedure or you don’t have the proper tools,
please take the unit to your nearest service center to
retorque the head bolts. This is a very important step
to insure the longest life for your engine.
NOTE: Only perform this adjustment after the first
50 hours of operation. The head bolts will need no
further adjustment.
• Torque sequence Is as follows: A, B, C, D, E (star
pattern).
C
NOTE: You must hold the rocker arm jam nut In place
as you turn the pivot ball stud.
Adjusting Valve Clearance
After the first 50 hours of operation, you should adjust
the valve clearance In the engine.
IMPORTANT: If you feel uncomfortable about doing
this procedure or you don’t have the proper tools,
please take the unit to your nearest service center to
have the valve clearance adjusted. This is a very
important step to insure the longest life for your
engine.
To adjust valve clearance:
• Make sure the engine is at room temperature.
• Make sure that the spark plug wire is removed from
the spark plug and out of the way.
• Remove the breather tube from the valve cover.
• Remove the four screws attaching the valve cover
with a #2 or 3 phillips screwdriver.
• Make sure the piston is at Top Dead Center (TDC)
of its compression stroke (both valves closed). To
get the piston at TDC, pull on the recoil handle
slowly watching the piston through the spark plug
hole. As you pull on the recoil handle the piston
should move up and down. The piston is at TDC
when it is up as high as it can go.
• Using a 10mm wrench, loosen the rocker arm jam
nut. Use an 8mm alien wrench to turn the pivot ball
stud while checking clearance between the rocker
arm and the valve stem with a feeler gauge.
Correct clearance Is 0.002-0.004 Inch
(0.05-0.1mm).
When valve clearance Is correct, hold the pivot ball
stud in place with the alien wrench and tighten the
rocker arm jam nut. Tighten the jam nut to
65-85 inch-pounds torque. After tightening the jam
nut, recheck valve clearance to make sure It did
not change.
Reattach the valve cover, making sure the gasket
between the valve cover and cylinder head is in
place. Start all four screws before tightening or you
will not be able to get all the screws In place.
Reattach the breather tube.
Reattach the spark plug wire to the spark plug.
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