hub re-greasing

[funky technician]

i was just wondering if you can regreese the front hubs (with them off the car) without splitting them apart, if i force enough grease in through the inner bearing, will it go through to the outer bearing or is there something in there to prevent grease transfer between bearings

[mechanicaldj]

not advisable


the outer seal could pop out

[funky technician]

I'm only using my thumb, no air pressure, (i know it sounds tedious) and rotating the rotor as i press the grease in by hand, will it reach the other bearing?

[TominMO]

I'm only using my thumb, no air pressure, (i know it sounds tedious) and rotating the rotor as i press the grease in by hand, will it reach the other bearing?

Highly unlikely, or that would be the standard procedure if it worked.

[blkfordsedan]

Why do you feel you need to add grease to the hubs? They are a sealed assembly and do not need to be re-greased unless you have a seal that is bad. Too much grease is as bad as not enough. It can cause the rollers to slide and actually run hotter. It can also lead to a blown seal which lets contaminates in. If you are not having issues I wouldn't worry about it. If you are having issues (like the hubs running hot or making noise), then the damage is already done (elevated temp and noise are symptoms) and your best bet is to pull them off and install new bearings and seals.

[sanjeet]

Remember the golden rule and only fill the bearings two thirds of the available space...so its strip down to do it properly and a waste of time repacking used bearings...once removed they should be replaced.

[Britstiva]

Why do you feel you need to add grease to the hubs? They are a sealed assembly and do not need to be re-greased unless you have a seal that is bad. Too much grease is as bad as not enough. It can cause the rollers to slide and actually run hotter. It can also lead to a blown seal which lets contaminates in. If you are not having issues I wouldn't worry about it. If you are having issues (like the hubs running hot or making noise), then the damage is already done (elevated temp and noise are symptoms) and your best bet is to pull them off and install new bearings and seals.

Not to hijack this thread... but I had just had a sinking feeling! I wonder if I added to much grease to my bearings when i reassembled them last week?!?!?!

[funky technician]

the reason i'm repacking them and not rebuilding them is because they only have 90 K on them and there in good shape and there is no play, so the bearings are good, but the grease, after 20 years, is like candle wax, so, i'm doing this to replenish the dryed out grease from factory, if i ran the hubs with the grease thats in them now, they wouldn't last 20K before it did reuin the bearings, and i know not to over pack them also because it affects the greases fluidity, but what i was wondering is if i force grease into one will it get to the other one. I also have no way of splitting them apart and don't want to just ruin them by running them iwth 20 years old grease (which i know is whats gonna happen, i've don't that already with a set that had old dry grease in them but good bearings, lasted 15 thousand and wore out) so giving that information, can it be done?

[blkfordsedan]

the reason i'm repacking them and not rebuilding them is because they only have 90 K on them and there in good shape and there is no play, so the bearings are good, but the grease, after 20 years, is like candle wax, so, i'm doing this to replenish the dryed out grease from factory, if i ran the hubs with the grease thats in them now, they wouldn't last 20K before it did reuin the bearings, and i know not to over pack them also because it affects the greases fluidity, but what i was wondering is if i force grease into one will it get to the other one. I also have no way of splitting them apart and don't want to just ruin them by running them iwth 20 years old grease (which i know is whats gonna happen, i've don't that already with a set that had old dry grease in them but good bearings, lasted 15 thousand and wore out) so giving that information, can it be done?

Makes sense. If you don't feel they will last the way it is then it's worth a try. I doubt you will ever get much grease worked past the first bearing by hand.

Can you buy a couple inner seals and just pop the old seal out and remove the bearing cone assembly? I don't remember if the inner bearing cone will come out or not. If so, then you could get at the hub center and clean out as much of the old grease and fill it with new grease. If not, then you may try some light grease in a syringe or one of those needle type grease guns.

[blkfordsedan]

Not to hijack this thread... but I had just had a sinking feeling! I wonder if I added to much grease to my bearings when i reassembled them last week?!?!?!

I wouldn't worry about it unless you packed them completely full. Even then, just occasionally feel the hubs with your hand after driving it a while. The wheel will be warm from the brakes, but if the bearings are running hot you won't be able to touch the center of the wheel.

[funky technician]

my old man just gave me a good idea, use a small amount of 90 weight oil (diff oil) and let it soak into the bearings, and as it soaks down through, and it will "re-hydrate" the old grease, i'm gonna try that, thanks guys, i'll let yas know

[WmWatt]

I recycle old bicycles which people seem never to grease. Many have seen little use. The grease if often dry as you describe.
If I can't get at the bearings I spray in penetrating oil to try to dissolve the old grease and them lubricating oil. But that's only because the cups are rusted in place and the bike would be scrap otherwise.
On my Festiva I'd take the wheel apart, clean, and re-grease properly.

[blkfordsedan]

my old man just gave me a good idea, use a small amount of 90 weight oil (diff oil) and let it soak into the bearings, and as it soaks down through, and it will "re-hydrate" the old grease, i'm gonna try that, thanks guys, i'll let yas know

Good idea. Grease is basically oil with a thickener base. As it gets hot, the oil seperates out and does it's job. Then, as it cools, the oil is absorbed back into the base. The old "dry" grease is actually the soap or thickener. The gear oil may work it's way back into the base, but it may have to get hot to do it. If the seals are good, I would flip the hub over and fill it up full w/oil, then let it sit for a day. I wonder if heating the oil first would help.............