The advantages are low friction and minimum power consumption, the possible use even in case of insufficient lubrication, operating range of -130º c to +200º c and much more: high chemical resistance and a low breakaway torque after standstill. Further, the PTFE, when heated, can” remember” its original form and return to it (phenomenon known as” plastic memory effect”).Therefore, this kind of seal do not need the old school metallic spring.
If necessary, lever it gently with a broad screwdriver blade, but take care not to bend the flange or damage the head.
Slacken the alternator or dynamo adjuster and pivot bolts, push the unit inwards and ease off the drive belt. Remove the belt completely.
DIN
There are a wide range of oil seals to select from for any number of uses, so this guide will break down the most common seals to help you choose the right one for whatever piece of machinery you are working on.
6. AMOUNT OF LUBRICANT: Seals perform better when lubricated but some machines will go through some dry spells. When this occurs using a leather or PTFE seal will be more beneficial as those type of seals can operate with less lubrication.
a)