Greasing rear wheel bearings

[cliff.b]

Decided to grease these today, as I was looking at the brakes and gave both sides a few pumps of the grease gun but I sort of expected old grease would emerge from somewhere, which it didn't. 

So I'm wondering, how do I know how much to pump in? Can you put too much and should it emerge from anywhere if you do?

 

 

[68vitesse]

Grease should come out through the inner seal drive shaft joint, this seals lips should face the differential, I always pump grease in untill it comes out so I know fresh grease has flowed through the bearings.

This is on swing axle cars don't know if rotaflex is different.

Regards

Paul.

[Colin Lindsay]

One of the first things I do is remove the grease nipple, if fitted, and trial-pump grease through it just to make sure it actually works. If I'm remembering correctly the manual says 'five strokes of grease gun' so that's what it gets.

I remember someone once querying if too much grease could come through on the inside of the brake drum and contaminate the brakes? Never saw it, but aways wondered myself. I'd like to think the design of the housing precludes that happening.

[Pete Lewis]

there is a oil seal to protect the shoe end of the job  the inboard oil seal should be as colin says back to front so grease can escape the lip seal but water cant go in 

and agree 4 to 5 pumps   ( and thats probably based on a bulk pressure garage greaser ??? )who knows   but it donst need much 

from memory and parts lists  there is no greaser on rotoflex hubs ..... sealed for life 

Pete

 

[cliff.b]

I think I need to check out my grease gun. I inherited it from my Father and it appears to work ok but maybe not under pressure. I pumped maybe a dozen times and no grease exited anywhere lol

 

[Pete Lewis]

if the inner  oil seal lets go there is a grease catcher held by the back plate bolts this drains grease( no it doesnt) out through a hole in the back plate to exit

under the bearing housing but its normally clogged with crud 

the most reliable old gun is a Wanner   get two one for oil one for grease 

best keep a look out at auto jumbles  for a cheapie   paid £8 for my last one   there s a whole load of guns at various prices 

[Badwolf]

I love the Wanner's. Got two off Fleabay for silly money. Because they're old and a bit messy people get rid. Just get a couple of new washers and clean them up and as good as new....and the feel of the grease between your fingers as you fill them up is absolutely.......!!!!

......Sorry lost it there for a minute.

[68vitesse]

In the last couple of weeks a new old stock wanner went for over seventy pounds including postage on eBay.

New ones do turn up bought this for a lot less a few years ago and can't persuade myself to use it,    co-op price label £4.16.

Regards

Paul.

 

[daverclasper]

19 hours ago, cliff.b said:

So I'm wondering, how do I know how much to pump in? Can you put too much and should it emerge from anywhere if you do?

I think when everything is ok then grease comes out of inner side of hub.  I guess if old hard grease is in there, that causes a blockage, then could blow a seal?.

Can that area be gently warmed with a hot air gun to make old grease flow (or other methods).

Dave 

[Colin Lindsay]

14 hours ago, daverclasper said:

I think when everything is ok then grease comes out of inner side of hub.  I guess if old hard grease is in there, that causes a blockage, then could blow a seal?.

Can that area be gently warmed with a hot air gun to make old grease flow (or other methods).

Dave 

It would take massive grease pressure to wreck a seal, so no panic there if you're using a grease gun. As for warming I'd reckon the bearings do heat up a bit as the car drives so grease immediately after use and it should be softer.

[cliff.b]

1 hour ago, Colin Lindsay said:

It would take massive grease pressure to wreck a seal, so no panic there if you're using a grease gun. As for warming I'd reckon the bearings do heat up a bit as the car drives so grease immediately after use and it should be softer.

That seems a good idea

[Pete Lewis]

think you grease gun  ....isnt 

Pete

[cliff.b]

Ok, got a new grease gun and tried again. Pumped maybe a dozen times then grease came out of a small hole in the underside of the trunnion near the backplate. Just above the brake adjuster.

Is this what I should be expecting?

[Pete Lewis]

thats the drain to supposedly stop grease escaping to the linings shouldnt let grease through when pumping unless the seal is leaking 

the clue that its taken that route probably leads to the inboard oil seal has been fitted wrong way round  and that grease has come into the back plate catcher 

may lead to the outer oil seal is leaking 

the  inboard seal is fitted inside out so grease should escape quite easily ,   i wouldnt worry too much but something to look at when you want a contest

over who wins you with a hub puller or the hub has a mind to stay put 

if youre concerned about too much grease whip a drum off and have a look and a clean  up of any excess

Pete

 

[cliff.b]

34 minutes ago, Pete Lewis said:

thats the drain to supposedly stop grease escaping to the linings shouldnt let grease through when pumping unless the seal is leaking 

the clue that its taken that route probably leads to the inboard oil seal has been fitted wrong way round  and that grease has come into the back plate catcher 

may lead to the outer oil seal is leaking 

the  inboard seal is fitted inside out so grease should escape quite easily ,   i wouldnt worry too much but something to look at when you want a contest

over who wins you with a hub puller or the hub has a mind to stay put 

if youre concerned about too much grease whip a drum off and have a look and a clean  up of any excess

Pete

 

Ok, thanks, that makes sense. I took the drum off again and no grease had made its way that far.

So if as you suggest, that seal has been fitted incorrectly, what, if any, are the implications?

[johny]

No major issue as far as Im concerned. It would be nice to push a bit of grease out of the seal to confirm its gone right through and also expel any dirt thats got in. If the seal is the wrong way round dirt/water can get in more easily than it should but then I dont suppose your going to be driving it in really arduous conditions...

[Colin Lindsay]

One I was looking at this morning had grease around the hub against the backplate - I actually thought it was sealant but it turned out to be blackened grease. It has obviously been forced out around the hub on the outside rather than the inside.

[cliff.b]

I'll take this off my list of serious things to worry about then lol

[cliff.b]

While we are in that area though, prior to the latest brake strip down I had noticed that the rear of the car looked significantly lower on the o/s so investigated while I had it stripped.

Thought it might be the spring but then found the shock only had about 4" of movement from fully closed.

After applying quite a lot of force it suddenly freed up, expanded to full length and then appeared to work normally. I have now put it back on the car and seems to be ok. 

so I'm wondering what happened to it and should it be replaced 🤔

[johny]

Strange, I wonder if the seal has been damaged though and it starts to leak oil? I take it the damping action felt good...

[cliff.b]

15 minutes ago, johny said:

Strange, I wonder if the seal has been damaged though and it starts to leak oil? I take it the damping action felt good...

Yes, it now feels exactly as I would expect it to. Car feels ok on the road and rear now level, as far as I can see.

[Pete Lewis]

can you get constipated shockers !!!!!!!!

you know its had a problem so just keep a eye on it . for any leak or odd behaviour

pete 

[cliff.b]

2 minutes ago, Pete Lewis said:

can you get constipated shockers !!!!!!!!

you know its had a problem so just keep a eye on it . for any leak or odd behaviour

pete 

Yes, I intend to. Very strange though.

[cliff.b]

Back to the bearing greasing issue, when I took the car out last week the rear started pulling to the right when braking and when I investigated yesterday I found grease has now worked its way into the drum. I presume this had happened after it warmed up.

I checked the other side as well and that also had grease ingress, but not as bad.

I cleaned everything up and now brakes working ok but have I caused any damage to the seals that should have stopped the grease getting there?

[Pete Lewis]

no the seals are either badly fitted or worn out so   a good clean up , poke the drain hole clear and less frequent greasing 

just one snag      needs the hub  flange removing to replace a seal    Grrrr  !!!

Pete