front hub bearings question

[milhouse]

I'm in the process of replacing the front hub oil seals and have a question that I've searched about but still haven't seemed to come up with a straight answer (and if the post is out there and I missed it, sorry!). The green bible calls for the hub to be "half filled with grease" before reassembly. Are the bearings lubricated with the grease/oil from the swivel housings, or are the two areas seperate (until seals start to leak)? I'm not trying to find out whether or not I should use grease or oil in the swivel housings - THAT I found pleanty of information/discussion about (and for the record I personally will be using gear oil in the swivel housings for the time being). What I want to know is for the hub bearings do I use the same lubrication as the swivel housings? If not, the "grease" that they call for, is that regular bearing grease or the CV grease? And if the oil from the swivel housing does in fact lubricate the bearings, do I need to do anything more than give everything a good coating of gear oil before I reassemble everything, then top off the swivel housing?

Oh, and in case it matters for the type of hubs I may have, my LR is a 1974 Series III 88".

Thanks!

[jac04]

The early design (II and IIA) hubs were oil lubricated. There was no oil seal between the swivel pin housing and the front hubs. The hubs had fill holes in them and you were supposed to fill the hubs full of oil after service.

Series III vehicles up to October 1980 still did not have an oil seal between the swivel pin housing and the hub. However, they did not have the oil fill hole in the hub. Therefore, you need to pack the bearings with grease (regular wheel bearing grease - not CV grease) to ensure they are lubricated at start-up. After time, this grease can become diluted with oil from the SPH.

From October 1980 on, there is an oil seal between the SPH and the hub. The hubs are grease lubricated only and should stay that way (as long as the oil seals do their job).

[TeriAnn]

I took the manual literally. i pack the wheel bearings, slather grease on the races & put a bunch of grease between the bearings (if a little is good, more is better and too much is just right). I assume oil will flow in during use but I don't want anything to dry out before it gets there in quantity. I figure as long as the oil seals work it doesn't hurt to have too much grease but it could hurt to not have enough.

i use molly axle grease.

[jac04]

I figure as long as the oil seals work it doesn't hurt to have too much grease.

Actually, too much grease can be very bad for bearings.
If you packed the hubs full of grease the bearings will be over-lubricated. Seems impossible, right? However, if the lube in front of the bearing rollers can't get out of the way fast enough, it forms a 'wave', and the rollers can skid. Also, the bearings will create excessive heat as they try to rotate when the hub is completely packed with grease. As the bearings heat up excessively, the grease would expand and possibly pop out the seals (at least on the later SIII type). Overheating the grease will also cause premature breakdown of the lubricant. All bad stuff. More is not better when it comes to greasing bearings.

[mearstrae]

I have also found on many other applications that too much grease, on high speed bearings, will actually cause the assembly to heat up (Bad things to follow...). A good quaility grease is important, synthetics that have a water proof base are nice. Just pack the bearings and install, the rest will take care of itself.

'95 R.R. Classic LWB
'76 Series III Hybrid 109
'70 Rover 3500S

[milhouse]

Thanks! This is exactly the information I was looking for!

[antichrist]

Even the Series III, not sure up to which year, but definitely up through '79, have the hub oil fill hole. You just have to remove one of the drive flange bolts to get to it. IIRC, it's the one that is in line with a wheel stud.
I use gear oil and am in fact going to switch my coilers to it once I use up this case of Pyroplex Blue.