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On 5 Oct 2004 at 7:50, Roush, Norman wrote: > 1) Are the front bump stops replaceable? Mine are torn but I cannot see > how to remove/replace them. Yes, they are just pushed on top of steel mushrooms. However, the steel mushrooms rust, and sometimes they pull off with the rubber caps when you try to replace the stops. If you're in a rust zone, be careful. > 2) When installing front hubs is it necessary to fill the void between > the inner and outer bearings with grease? It is a good idea to fill the inner cavity with grease. Don't fill it ALL the way full, and don't put any in the outer hub cap or in the space inboard of the inner bearing. Clean and grease the surface that the seal runs on, and smear a layer of grease on all the metal parts in the cap, just to prevent rust. Grease is a mixture of oil and soap. The soap component has no lubricating properties and is nothing more than a stiffener and a medium to carry the oil. Oil will slowly separate from the soap in use and flow into the bearing where it is used to lubricate. Extra grease is just a reservoir for extra oil which will keep your bearing lubricated longer. You must NOT completely fill ALL the volume around the bearing with grease. There needs to be enough air space around the bearing that the bearing can push the excess grease out of its way when it is moving. This is called "channeling" and is normal and necessary for good bearing lifetime. If there is not enough room for channeling to occur, then there will be excessive energy used up in viscous stirring of the grease and some high speed bearings can even overheat and die. It is questionable as to whether this would ever happen to automotive wheel bearings in normal street usage, but why take a chance. The main thing to keep in mind when you put your hubs back together are twofold: 1) Clean and polish the steel area where the seal runs. If that area is rough with rust, it will wear thru the seal almost instantly. Likewise, don't put the seal on dry. Put grease on the seal lips and on the steel area where the seal rides. 2) Adjust the wheel bearings so that there is SOME play in all positions. A minimum amount of play is desirable, but the most important thing is to make sure that there is never a preload on them. Of course, you need to make sure that everything goes together clean. A little bit of dirt or grit of any kind makes the whole job pointless. -- Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~