These washers have a dual function, as an adjustment washer for the distributor shaft for type 1, type 3, CT/CZ and Waterboxer (WBX) engines and as a rocker arm washer that is only used for type 1 25 hp and 30 hp engines.
Distributor shaft adjustment washer:
Between the distributor driveshaft and the crankcase, there are in most cases two 0.60 mm washers. If the crankcase has already been overhauled, these washers may be of a different size or there may only be one thicker washer. If the axle is 80.3 mm long (to the edge where the washers will be placed) and the bore in the crankcase is 126.10 mm (to the point where the washers will be placed), you are dealing with a crankcase that has not yet been machined, in which case you will need two 0.60 mm washers. The washers cannot be bent (don't use spring washers) or worn, if they are, you must replace them.
Washer for rocker arm:
To protect the spacer sleeve from the effects of the rocker arm locking clips, a washer is mounted between the two. During a complete overhaul, leave nothing to chance, the locking clip may act on the washer and cause excessive play. It is strongly recommended to replace the locking clip with the washer. For each rocker arm, you need one washer, to replace all the washers of all rockers, that makes a total of 8 pieces.
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