Cylinder Head - Bottom View

Fig 1: Cylinder Head - Bottom View

Courtesy of GENERAL MOTORS CORP.

Service Call Out	Thread Size	Insert	Drill	Counterbore Tool	Tap	Driver	Drill Depth (Maximum)		Tap Depth (Maximum)
J 42385-							MM	(IN)	MM	(IN)
1	M12 x 1.75	865	856	857	858	859	17	0.670	14	0.551
2	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
3	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
4	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
5	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A