Thread: Swivel hub breathers - any one done it?

Originally Posted by Blknight.aus

not going to happen primarily because of shape of the axle tubes and the fact that the diff is a lot lower than the axle centers. On top of that the bearing that sits on the end will keep most of the oil back at any rate.

If it does happen what happens to your hub bearings and UJ when you loose the oil out of the hub.

IF you know you have a problem like that and you're running oil fed bearings its a lot easier to top up through the diff anyway along sides of which you now have an extra liter or so of oil that can get out there to help keep it all lubricated.

I'm more worried about the amount of oil that's trying to lubricate my brakes, than what's left to lubricate the diff and cv's.
I've had a hub seal go before on the front left when driving. This is where the road sends a good supply of diff oil, even the comparitively small amount that the swivel contained caused a huge mess.

in for a little leak on the brakes in for a big one...

On my old 200 TDI I got a longer filler bolt and drilled it out and fitted a banjo fitting with barb. I then just ran an air line.

I’ve pulled the inner oil seal on the back of my current TD5 2001 Def, so the flanges/bearings run in oil. I was gong to do the same on the front but was told not to.

From what I’m reading there is no reason not to pull the inner oil seal and run the diff oil through to the flanges. The main diff breather would then equalise the pressure. You would however need to keep the seals in good/working condition

The only negative I can think of is that there is no drain plug on the new swivel so you would rely on draining the diff oil regularly. Noting that there would always be some residual oil in the swivel housing.
What do you think

Originally Posted by Blknight.aus

I use one of those air matress pumps that draws air from somewhere safe and then bung the hoses into the outlet of the pump. gives about 1psi

Originally Posted by Dougal

Pressure fed breathers are a good idea (up to about 2psi anyway).
But one reason I've never felt comfortable pulling the inner seals is the ability to then lose a whole diff full of oil through a dead hub or swivel seal.

Keeping them in three seperate segments does minimise damage in that unlikely event.

G'day Blknight.aus,

Dougal, g'day mate, hope e'rything is good down on the coast.

Am getting used to the idea of a slight pressure charge in the diff and swivel hubs. I'd still prefer not to need pressurised axle cavitys but am mulling it over.

However, I am currently set against pulling all the internal seals out and having one long oil chamber. I simply don't see enough advange for it to warrent the risk of getting a leak in the 'last' seal and thereby getting lots of oily water, or lots of watery oil...

Originally Posted by discowhite

... snip ...
the easiest place in the front to let water in is the rubber end cap, i just run a bit of sillicon around the inside b4 i put it back on.

cheers phil

G'day Phil,

yes, agreed on that one. Am always weary of deep rutted tracks taking the end caps off. I too use silicon to seal and also at times use cable ties to give the seal an additional bit of strength. Would love to be able to afford the new one piece drive flanges that do away with the seal caps.

Originally Posted by scott oz

On my old 200 TDI I got a longer filler bolt and drilled it out and fitted a banjo fitting with barb. I then just ran an air line.

I’ve pulled the inner oil seal on the back of my current TD5 2001 Def, so the flanges/bearings run in oil. I was gong to do the same on the front but was told not to.

From what I’m reading there is no reason not to pull the inner oil seal and run the diff oil through to the flanges. The main diff breather would then equalise the pressure. You would however need to keep the seals in good/working condition

The only negative I can think of is that there is no drain plug on the new swivel so you would rely on draining the diff oil regularly. Noting that there would always be some residual oil in the swivel housing.
What do you think

G'day Scott Oz,

I like the idea of a banjo fitting on each filler plug. That'd make for the good angle up and back over the hub and out of the way and would be easy enough to do in my garage at home.

Yes, I am thinking of going back to greased front wheel bearings but am as yet undecided. Haven't had a problem as yet with water getting in there as I always seem to check it in time before the contamination gets from the swivel hub into the bearings.

Well, so far my thinking is insert breather tubes on each of the swivel hub filler bungs, and then 'tee' each of these breathers to the main diff breather on the axle housing so only one tube runs up into the firewall console area from the axle. Retain all the main oil seals and maintain in good shape so as to keep the three distinct oil resevoirs. Thinking of reverting back to greased wheel bearings.

Is there no drain plug on new swivel hubs??

Thanks to all, appreciate the feedback. More ideas welcome at any time.

Cheers,

Phil

Originally Posted by windsock

G'day

Is there no drain plug on new swivel hubs?

Phil

Grease in my 2001 TD5 Def with no way of getting the grease out. I gather that if water gets in it doesnt take long for problems to start.

If I wished to go seperate swivel oil I'd have to retro fit old housings or tap a fill and drain points in the existing housing. The alterntive is to remove the inner seal.

decisions, decisions, decisions.

no...

ABSOLUTELY NO...

DO not go back to grease once youve gone to oil...


thats like being handed the holy grail of driveline life and saying... no, one day the seal might fail and I might get some oil on some very cheap brake pads......


IF brake pads get greasy you can generally work around it

contaminated oil fed bearings will let you know because the whole assembly gets contaminated and when you check the oil you see porridge and think "what ho? my oil looks like a bad scottish breakfast.. something is not as it should be."

with grease fed bearings you dont notice that the grease in the bearings has picked up water because it hasnt migrated to the one shot grease yet so you drive along and find that all of a not so sudden the bearings have collapsed, eaten the stub axle and you cant fix it.


there is exactly 1 reason to have greased bearings and then thats only temporary and that is if youve had to do a fix but the seal race is too buggered to support a dual lipped oil seal without killing it.

A mate of mine tapped breathers into his swivel housings. But he ran them all the way to the firewall, rather than just across to the diff. He also tapped them near the top. I wouldn't tap the fill plug as it is only just above the oil level (on all mine anyway...).

However, As Blackie and DW mentioned, pulling all the internal seals and running common breathers is the way to go. I have had it on all my landies for years.

Dougal, no need to be worried about brakes - you have discs after all!!! I blew a seal on my IIA once in a major way, I think the overall amount of oil leaking out was only slightly more than the swivel volume, especially when you are aren't driving on side slopes.

G'day,

Just getting a tad confused with terminology and perhaps there is a bit of discussion at cross-purposes regarding where grease goes and where oil flows etc. Could be just me though...

Thought pictures may clarify for myself anyway so here goes.


Figure 1.


Figure 2.

I am thinking of retaining all the seals shown in both figures (Figure 1 - 5, Figure 2 - 8,23) but currently I do not have the constant velocity shaft seal in place (Figure 2 - 23), and therefore oil flows from the swivel ball into the hub and lubricates the wheel bearings.

I am thinking of replacing this seal only (Figure 2 - 23) such that I can retain oil in the swivel hub and grease the bearings instead of the current oil-washed system. I would retain the intermediate/axle shaft seal.

I think there is much discussion involving removing this intermediate seal (Figure 1 - 5 & Figure 2 - 8) and thereby allowing oil to flow somewhat slowly past the axle shaft into the swivel hub.

I don't necessarily like this idea as it would allow cross-contamination of water throughout the axle housing should I get an ingress leak somewhere.

Blknight.aus, you mention not going back to grease in the hub once oil has been used. Are you referring to the wheel bearing hubs (Figure 2 - 6) or the swivel ball CV hub?

If I was going to go back to grease I would be planning to use Moreys water proof hi-temp grease for this purpose on the wheel bearings only (Figure 2 - 6). I would maintain the oil washed CV, and retain the intermediate seal so that there remains three distinct oil chambers. Here in NZ, most of my driving is very wet and there is virtually only back-road dry driving available. I cross rivers a lot and I get water ingress into the swivel ball CV area. By placing breathers on these I hope to minimise this but should it still occur I would still want to retain seperate oils so as to minimise the damage. By removing the intermediate seal as proposed by some I would indeed allow the central breather to operate over the whole axle but I would be reliant on there being a free flow of air between the swivel and axle housing. This 'space' would be thick with 90EP oil and therefore may become blocked to alllow for the quick air flow indiced by rapid temperature change (river water is currently single digit temp in the mornings and going to about 10-11 Deg C by afternoon) of the axle/swivel air spaces would see water still dramn in. My feelings is separate breathers would allow free flow of air to each segment. I appreciate what Isuzurover says about the plug being just above the oil level.

Much to think about. I will mull things over more before I do anything I think.

Hope the pictures clarify for others as well as they have for me (should have perhaps put them up earlier).

Cheers,

Phil