Valve Guides
Check the guides carefully and inspect them for any cracks, chips or breakage. Also if the
guide is a removable style (as in most aluminum heads), check them for any looseness or
evidence of movement. All of the guides should appear to be at the same height from the
spring seat. If any seem lower (or higher) from another, measure the heights to determine
if the guide has moved.
Mount a dial indicator onto the spring side of the cylinder head. Lightly oil the valve stem
and insert it into the cylinder head. Position the dial indicator against the valve stem near
the tip and zero the gauge. Grasp the valve stem and wiggle towards and away from the
dial indicator and observe the readings. Mount the dial indicator 90 degrees from the initial
point and zero the gauge and again take a reading. Compare the two readings for an out
of round condition. Check the readings against the specifications given. An Inside
Diameter (I.D.) gauge designed for valve guides will give you an accurate valve guide bore
measurement. If the I.D. gauge is used, compare the readings with the specifications. Any
guides that fail these inspections should be replaced or machined.
Reading stem-to-guide clearance
Valve Seats
A slightly worn and pitted surface where the valve face contacts the seat will typically be
apparent when valve seats are inspected. Inspect the seat carefully for severe pitting or
cracks. A seat that is badly worn will be recessed into the cylinder head. A severely worn
or recessed seat may need to be replaced. All cracked seats must be replaced. Use a seat
concentricity gauge to check the seat run-out. If run-out exceeds specifications the seat
must be machined. If a specification can not be found, use 0.002 in. (0.051mm) as a
general rule of thumb for concentricity.
Summary of Contents for TrailBlazer
Page 1: ......
Page 26: ...Fig 3 Typical body and undervehicle maintenance locations Refer to chart for descriptions ...
Page 29: ......
Page 30: ......
Page 31: ......
Page 175: ...Spring free length check Valve spring squareness check ...
Page 192: ...Front of piston mark ...
Page 361: ...5 3L Engine Except Saab Underhood Fuse Block 2003 2005 Early Production ...
Page 469: ...Removing the outer band from the CV boot Removing the inner band from the CV boot ...
Page 470: ...Removing the CV boot from the joint housing Clean the CV joint housing prior to removing boot ...
Page 471: ...Removing the CV joint housing assembly Removing the CV joint ...
Page 472: ...Inspecting the CV joint housing Removing the CV joint outer snap ring ...
Page 473: ...Checking the CV joint snap ring for wear CV joint snap ring typical ...
Page 474: ...Removing the CV joint assembly Removing the CV joint inner snap ring ...
Page 475: ...Installing the CV joint assembly typical ...
Page 553: ...9 Torque the lug nuts to specification 10 Lower the vehicle ...
Page 556: ...Toe in Frame Misalignment Frame misalignment ...
Page 588: ...Bleeding caliper ...
Page 624: ...Manifold gauge set components Refrigerant recovery recycling station ...
Page 676: ...A C Specifications ...
Page 677: ......