Engine Block - Front View

Fig 1: Engine Block - Front View

Courtesy of GENERAL MOTORS CORP.

Service Hole Location	Thread Size	Drill	Counterbore Tool	Stop Collar	Tap	Driver	Insert	Drill Depth (Max)		Tap Depth (Min)
J 42385-400 . See Special Tools .								mm	(in)	mm	(in)
1	M 6 x 1	405	n/a	407	203	204	205	30	1.182	26	1.024
2	M 6 x 1	201	202	n/a	203	204	205	18	0.709	14	0.551
3	M 6 x 1	201	202	n/a	203	204	205	22	0.866	18	0.709
4	M 8 x 1.25	206	207	n/a	208	209	210	23	0.906	18	0.709
5	M 16 x 1.5	405	n/a	407	203	204	205	24	0.945	16	0.630