Bearing selection

1 Main bearings for the engines of Fiat Punto described here are available in standard sizes and a range of undersizes to suit reground crankshafts. Refer to your Fiat dealer or engine reconditioning specialist for details.

Refitting

2 Clean the backs of the bearing shells, and the bearing locations in both the cylinder block and the main bearing caps or lower crankcase.
3 Press the bearing shells into their locations, ensuring that the tab on each shell engages in the notch in the cylinder block or bearing cap/lower crankcase. Note that the bearing shell incorporating the thrustwashers is fitted to the centre main bearing shell location in the cylinder block of Fiat Punto. Take care not to touch any shell's bearing surface with your fingers.
4 Wipe dry the shells with a lint-free cloth, then liberally lubricate each bearing shell in the cylinder block with clean engine oil.
5 Lower the crankshaft into position so that Nos 2 and 3 cylinder crankpins are at TDC; Nos 1 and 4 cylinder crankpins will be at BOC, ready for fitting No 1 piston. Proceed as follows according to engine type.

SOHC (8-valve) engines of Fiat Punto

6 Lubricate the lower bearing shells in the main bearing caps with clean engine oil.
7 Fit the main bearing caps to their correct locations, ensuring that they are fitted the correct way round (the bearing shell tab recesses in the block and caps must be on the same side). Insert the bolts loosely.
8 Tighten the main bearing cap bolts to the specified Stage 1 torque wrench setting. Once all the bolts have been tightened to the Stage 1 setting, angle-tighten the bolts through the specified Stage 2 angle, using a socket and extension bar. It is recommended that an angle-measuring gauge is used during this stage of the tightening, to ensure accuracy.
9 Check that the crankshaft rotates freely.
10 Prise out the crankshaft oil seal and fit a new seal to the housing (see illustrations).



Use a screwdriver to prise out the oil seal...



... locate the new oil seal in the housing...



... and use a block of wood to drive it in - SOHC (8-valve) engines


11 Lubricate the oil seal lips then carefully locate the oil seal housing into position, using a new gasket. If the oil seal housing was originally fitted without a gasket, apply a 3.0 mm bead of RTV silicone sealant to the housing flange (see illustration). Refit the retaining bolts of Fiat Punto engine and tighten them securely.



Application area for silicone sealant on crankshaft oil seal housing – SOHC (8-valve) engines


12 Continue with engine reassembly.

DOHC (16-valve) engines of Fiat Punto

Note: At the time of writing there was conflicting information from the manufacturer concerning the lower crankcase retaining bolt torque setting. As it was not possible to confirm the validity of the figures given in the Specifications, consult a Fiat dealer for latest information.
13 Thoroughly degrease the mating surfaces of the cylinder block and the lower crankcase. Apply a 2,0 mm bead of RTV silicone sealant to the lower crankcase mating surface (see illustration).



Apply a 2.0 mm bead of silicone sealant to the lower crankcase mating surface - DOHC (16-valve) engines of Fiat Punto


14 Lubricate the lower bearing shells with clean engine oil, then refit the lower crankcase, ensuring that the shells are not displaced, and that the locating dowels engage correctly.
15 Install the ten inner (main bearing) bolts, and the ten outer bolts securing the lower crankcase to the cylinder block. Screw all the bolts in until they are just making contact with the lower crankcase.
16 Working in sequence, tighten the ten inner (main bearing) bolts to the Stage 1 torque setting given in the Specifications. Once all the ten inner bolts have been tightened to the Stage 1 setting, angle-tighten the bolts through the specified Stage 2 angle, using a socket and extension bar, it is recommended that an angle-measuring gauge is used during this stage of the tightening, to ensure accuracy (see Illustrations).
17 Working in the same sequence as for the inner (main bearing) bolts, tighten the ten outer bolts to the Stage 1 torque setting, then through the Stage 2 angle.



Lower crankcase retaining bolt tightening sequence - DOHC (16-valves engines)



Tighten the ten inner lower crankcase bolls to the Stage 1 torque setting using a torque wrench ...



... then through the Stage 2 angle using an angle-measuring gauge – DOHC (16-valve) engines of Fiat Punto


18 With the lower crankcase in place, check that the crankshaft rotates freely.
19 Lubricate the oil seal lips then carefully locate a new oil seat housing into position (see illustration). Refit the retaining bolts and tighten them securely.
 



Lubricate the oil seal lips then locate a new rear oil seal housing into position - DOHC (16-valve) engines


20 Continue with engine reassembly.