Not all type 1 engines are equipped with a bearing on the crankshaft pulley side, but the pulley has grooves that rotate in opposite directions so that the engine oil is stopped or pushed, so to speak. In the event of an oil leak, the grooves in the pulley may be worn or, in the worst case, the crankcase may be worn and the oil will no longer be stopped. In the latter case, a Sand Seal type pulley offers a solution. This involves placing an aluminum ring with a replaceable seal in the crankshaft housing (without disassembling the engine) that will ensure the oil seal. After the assembly of the Sand Seal pulley, which no longer has any grooves but closes on the seal, the leak is solved for good. If the seal leaks, you can easily replace it with a new one (see the Spare Parts tab). It is also possible to mount a machined-in sand sealing pulley, but to do this it is necessary to machine the crankcase on the pulley side so that the retaining ring is mounted directly in the crankcase. If you are overhauling your engine, it is wise to choose this option. The assembly of a sand sealing pulley provides a much better sealing than that of a standard pulley, which is why sand sealing pulleys are often used as standard in the cross country and racing world.
All sand seal pulleys are made of polished aluminum and have a black engraved scale. The pulleys have a diameter of 170 mm, this is the original only on 1200 and 1300 cc engines are used. The 1500 and 1600 cc engines are originally equipped with a 177 mm pulley, the larger diameter gives a higher cooling power required for the higher engine power of these engines. A pulley with a lighter weight and smaller diameter is the key to reaching maximum engine power, hence the frequent use of these 170 mm pulleys on 1500 and 1600 cc engines. However, there is a disadvantage: the cooling capacity is reduced by the smaller diameter, which is why the 1500 and 1600 cc engines are not mentioned in the list.
Attention! With bolted pulleys, it is necessary to mount a longer pulley bolt, this type of pulley comes a little further forward and the length of the standard bolt has become too short. Order it separately, the bolt is listed under the options tab. In addition, the retaining ring for the machine-in pulley and the bolted pulley ring must be equipped with a liquid seal during assembly, order this seal in addition (see the options tab).
Note : Other versions are listed under the Alternatives tab (other than the one you have selected now).
Instructions
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