Engine Repair Work Example 7

WorkKey Level: 4
NATEF Automotive Tasks: I.B.8

You measured the installed height of a set of valve springs and have come up with the following:

Spring	Height (inches)	Acceptable	Not Acceptable	Shim Thickness
1	1.85
2	1.71
3	1.75
4	1.82
5	1.78
6	1.69
7	1.72
8	1.79

The manufacturer’s spec for installed height is 1.75 inches + 0.030 inch.  Complete the table above to determine whether each spring is acceptable.  Then select the most appropriate shims to do the job from the list below.

0.005"

0.010"

0.015"

0.030"

                                                              

Solution:

The range of acceptable springs is as follows:
1.75" + 0.030" = 1.78"
1.75" – 0.030" = 1.72"
(1.72" < spring height < 1.78")

Spring	Height (inches)	Acceptable	Not Acceptable	Shim Thickness
1	1.85		X
2	1.71		X	0.015
3	1.75	X
4	1.82		X
5	1.78	X
6	1.69		X	0.030
7	1.72	X
8	1.79		X