path said:
As eliallen says, "You need to put enough new grease to force the old grease out through the outside bearing".
I put bearing buddy's on my TT. Turned out to be mistake. As your sitting at a red light with your brakes on your brakes are getting hotter and hotter. This caused mine to thin out and then leak out from the bearing and on the wheel and on fender etc as you travel. What a mess to clean off. If you are still unsure how much is enough take it somewhere and tell them you want to watch in case you ever need repair on the road broke down somewhere.
You tube has a few vid's about it.
http://www.youtube.com/results?search_query=grease+bearings&oq=grease+bearings&aq=f&aqi=g1&aql=&gs_sm=12&gs_upl=4291l9288l0l12575l15l15l0l1l1l0l81l939l14l14l0
Your brakes should not get hot sitting at a red light because nothing should be moving at that point so there is no friction. Your brakes could get hot from a lot of braking down a big incline or your hubs themselves could get hot if the bearings are worn or dry, particularly at high speeds. Both of these could cause the hub to heat up and the grease to thin out and have an easier time making its way past the rear seal. This is why it is important to keep the seals in good shape and to use high temperature bearing grease.
After the bearings are removed and thoroughly cleaned, on should inspect them for wear and make sure they rotate freely. You should also clean and inspect the bearing races which is what the bearings ride up against on the inside of the hub. If these are scored or pitted, they should be replaced and if they are worn, your bearings are likely to be in line for replacing as well. If you run your fingernail along the bearing surface of the race and it catches, you should replace the race and bearing. The rear seal should be flexible and absent of cracks or it should be replaced as well. A bad seal will leak and grease can contaminate the brake shoes and impact braking power.
When repacking bearings, spray down the inside of the drum along the inside circumference and also the flat part of the drum to wash off any grease or grime that can affect the brakes or the electromagnet that engages the brakes.
If everything is in good order, you are supposed to be able to flood the inside of the hub with grease on the EZ-Lube bearings. The grease flows through the spindle to the inside bearing and the rear seal keeps it from going out the back into the brake mechanism. The grease flows forward to the outside bearing and out around the castle nut. This means the entire hub is filled with grease and if everything is sealed up good, you should be able to force out the old grease without removing the hub. Use a good quality waterproof grease that will hold up to both heat and moisture.
However, I wouldn't do this too many times before removing the hub so you can inspect the condition of the seal. If the seal is not doing its job, you will spray grease all over the brake system which would be a bad thing.
It is a good idea to take a look at your wheels and hubs at every stop to make sure they are not heating up. If they are, you need to attend to those bearings before you do some damage.
If you do need to replace the bearings and races, you can buy a bearing kit that contains both bearings, both races and a new seal for around $12. Just make sure to save the old races to use to drive in the new ones. One good tip is to cut a slit in the race (a radial cut all the way through, about 1/8 inch wide) so the old race comes out easy after driving in the new one.
