Bobcat 741 - Page 313

VALVES (Cont'd)
Valve Guide
The tool listed will be needed to do the following
procedure:
MEL 1298 -
Valve Guide Installation & Removal
Check the valve guides for wear with a dial indicator [A] .
If the movement is more than listed specifications,
replace the valve guide.
Intake:
Standard . . .. .. . 0. 0012-0.0024 inch (0,03-0,06 mm)
Service Limit .............. . . 0. 004 inch (0,15 mm)
Exhaust:
A
Standard .... .. . 0.0020-0.0035 inch (0,05-0,09 mm) B
Service Limit ...... .... .. .. .. 0.006 inch (0,15 mm)
NOTE: Make sure to check the valve stem for wear
before replacing the valve guide.
Heat the cylinder head to a temperature of about 480 ° F.
(250°C.). Use the correct tool and press the valve guide
out of the
cylinder head [B).
Check the specifications, Section 8 for the correct
oversize
valve guide.
Ream each bore in the
cylinder head to the correct size
at normal temperature. Heat the cylinder head
to about
480° F. (250°C.) and quickly press the valve guide into
position using
the correct special tool [C] . The correct
tool, ensures the guide is pressed in the specified depth.
Valve Spring
Check the free length and inclination of the exhaust and
intake springs
(0).
New Free Length. . . . . . . . . . . .. 1.811 inches (46 mm)
Service Limit ........ .. .. . . -0 . 039 inch (-1 ,0 mm)
Inclination . ....... . .. . ... .......... .... ... .. . 1.5°
Service Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3°
Added Sept. 90
-7D-3~
c
D
0.40 inch
(10 mm)
~
t
EHl9763
0.539-0.563"
"fj\3mm
l
Square
EHl8208
741, 742, 743, 7430S Bobcat Loader
Service Manual