Crankshaft Check Opel Arena I

Crankshaft, Check

Crankshaft axial clearance - use dial indicator with magnetic base.

Axial clearance = 0.07 to 0.23 mm.

Replace thrust washers on number 2 main bearing if axial clearance is incorrect.

Thrust washers are available in different thickness:

2.30 - 2.35 - 2.40 - 2.45 mm.

Crankshaft journals and bearings.

Oil ports for obstruction.

Oil seal contact surfaces for excessive wear and damage.

Journals and crank pins for wear and damage.

Two methods for measuring bearing free play are described - the Plastigage method and the micrometer and gauge method. The two procedures are suitable for measuring both con-rod and main bearing free play.

For both methods, ensure con-rod caps (arrowed) and main bearing shells are identified prior to removal to ensure assembly to correct positions.

Plastigage method

Crankcase with main bearing shells - bolts.

Lightly coat journals and bearings with engine oil to prevent Plastigage from tearing when caps and crankcase are removed.

Lay a length of Plastigage across width of journals and install con-rod caps and shells, and crankcase and shells - use old bolts at this stage, tighten crankcase bolts uniformly.

Do not allow crankshaft to rotate.

Con-rod cap bolts - 48 Nm/35 lbf ft.

Crankcase and shells and con-rod caps and shells - bolts.

Width of Plastigage - use scale supplied with Plastigage.

If con-rod bearing clearance or main bearing clearance is excessive, check previously measured crankshaft-journal diameters.

Plastigage from journals.

Lightly coat journals and bearings with engine oil.

Con-rod caps and bearing shells, and crankcase and bearing shells - use new bolts.

Con-rod cap bolts - 48 Nm/35 lbf ft.

Micrometer and gauge method

Crankshaft removed.

Ensure components are assembled together correctly in original positions - see identification numbers (arrowed).

Con-rod caps and bearing shells to con-rods - bolts.

Con-rod and crankshaft main bearing diameters at three points I, II, III (arrowed).

Divide the sum of the three measurements to obtain a mean diameter.

Con-rod caps and bearing shells from con-rods - bolts.

Crankcase from cylinder block - bolts.

Crankshaft and con-rod bearing journals at points I and II. Divide the sum of both measurements by two to obtain a mean diameter.

Crankshaft must be replaced if mean diameter of main or con-rod journals is below specified limit - see ‘Technical Data’.

If crankshaft is serviceable, subtract crankshaft mean journal diameters from corresponding bearing shell mean diameters to determine bearing clearance.