Engine Block - Bottom View

Fig 1: Engine Block - Bottom 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 10 x 1.5	417	n/a	n/a	418	419	420	49	1.93	42	1.655
2	M 8 x 1.25	206	207	n/a	208	209	210	30	1.182	25	0.985
3	M 6 x 1	201	202	n/a	203	204	205	22	0.866	18	0.709