The axial clearance of the crankshaft must be adjusted between 0.07 and 0.13 mm and the wear limit is 0.15 mm.
Axial play is measured with a dial gauge. If the axial play is not accurately adjusted, the motor can suffer severe and irreparable damage. Play is adjusted using adjusting rings or shims located behind the flywheel, by first adjusting the axial clearance and then mounting the crankshaft retaining ring.
It is important that three shims are always fitted. The shims are available in different thicknesses to allow precise adjustment. Never use old, worn bushings, bushings with burrs or bushings that are no longer flat. This will make it impossible to determine the correct fit.
The inner diameter of these rings is 53.6 mm. Measure this diameter with Type 1 and Type 3 motors before ordering to ensure that your motor is actually dated according to the specified year of manufacture. With Type 4 or WBX engines, you don't need to measure this, they have never been modified. The exact engine number in 1966, from which the 53.6 mm inner diameter rings are used, is listed below.
Engines type 1 :
1200 cc D 0 076 332
1300 cc E 0 004 201
1300 cc F 0 741 385
E type 3 engines:
1500 cc K 0 040 817
1500 cc M 0 000 300
1600 cc T 0 210 167
1600 cc P 0 000 800
Note: Adjustment of the crankshaft axial clearance should only be carried out when the engine is overhauled. Overhaul here means that new crankshaft bearings are fitted and the crankcase is in good condition (as the vast majority of engines require overhaul, it is also necessary to have the crankcase drilled in line and the axial bearing seat (1st main bearing) machined). In the case of existing engines, which are not recently overhauled, the axial clearance is often greater than 0.13 mm, for example 0.30 mm. The additional play here is caused by the wear of the crankcase and the 1st main bearing on each other. This play cannot be eliminated by means of the adjusting rings. Attempting to do so may cause serious damage to the engine. If there is too much axial play, overhaul is the only solution.
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