Valve Clearance Adjustment (Cont'd)
EM-128prose procedureSR (SR20DE/SR20DET) engine cylinder head.
Shim selection
- 21If valve clearance is not within specifications, select suitable shim(s) and rocker arm guide.How to select a suitable shim and a suitable rocker arm guideExample: When intake valve clearance (on the shim side) is 0.4 mm (0.016 in), determine the required shim thickness using the following equations:0.40 mm (0.0157 in) − 0.30 mm (0.0118 in) [Minimum standard value] = 0.10 mm (0.0039 in)2.55 mm (0.1043 in) + 0.10 mm (0.0039 in) [Actual shim thickness] = 2.75 mm (0.1083 in)Select a total of 2.75 mm (0.1083 in) thick shim(s).
IMPORTANT
Using a dial gauge, measure thickness (T) of the selected shim(s) and the rocker arm guide on a flat surface to make sure it is within specifications.
Shims and rocker arm guides are available in 81 different thicknesses ranging from 1.50 mm (0.0591 in) to 3.50 mm (0.1378 in) in increments of 0.025 mm (0.0010 in).
Shim selection (Cont'd)
- 22Remove camshafts, oil tubes and rocker arms in the order of steps 1 through 5 above.
- 23Remove the existing shim(s) and install the selected shim(s) and the rocker arm guide.
- 24After installing the required parts as outlined in steps 8 through 11 above, rotate the crankshaft until the camshaft surface is positioned in relation to the cylinder to be checked, as shown in figure.
SEM854D