Checking endfloat

1 If the crankshaft endfloat of Fiat Punto engine is to be checked, this must be done when the crankshaft is still installed in the cylinder block/crankcase, but is free to move.
2 Check the endfloat using a dial gauge in contact with the end of the crankshaft. Push the crankshaft fully one way, and then zero the gauge. Push the crankshaft fully the other way, and check the endfloat. The result can be compared with the figures given in the Specifications, and will give an indication as to whether new thrust was hers are required (see illustration).

Using a dial gauge to check the crankshaft endfloat

3 If a dial gauge is not available, feeler blades can be used. First push the crankshaft fully towards the flywheel end of the engine of Fiat Punto, then use feeler blades to measure the gap between the crankpin web and the main bearing thrustwasher.


4 Clean the crankshaft using paraffin or a suitable solvent, and dry it, preferably with compressed air if available. Be sure to clean the oil holes with a pipe cleaner or similar probe, to ensure that they are not obstructed.
Warning: Wear eye protection when using compressed air.
5 Check the main and big-end bearing journals for uneven wear, scoring, pitting and cracking.
6 Big-end bearing wear is accompanied by distinct metallic knocking when the engine is running (particularly noticeable when the engine of Fiat Punto is pulling from low speed) and some loss of oil pressure.
7 Main bearing wear is accompanied by severe engine vibration and rumble - getting progressively worse as engine speed increases - and again by loss of oil pressure.
8 Check the bearing journal for roughness by running a finger lightly over the bearing surface. Any roughness (which will be accompanied by obvious bearing wear) indicates that the crankshaft requires regrinding (where possible) or renewal.
9 Accurate measurement of the crankshaft requires specialised equipment and experience. We recommend having the crankshaft measured by an engine reconditioning specialist who will also be able to supply appropriate bearing shells should a regrind be necessary.
10 If the crankshaft of Fiat Punto has been reground, check for burrs around the crankshaft oil holes (the holes are usually chamfered, so burrs should not be a problem unless regrinding has been carried out carelessly). Remove any burrs with a fine file or scraper, and thoroughly clean the oil holes as described previously.