General Whats next .......Leaking Drive Shaft Oil Seal !

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General Whats next .......Leaking Drive Shaft Oil Seal !

These types of seal tend to harden with heat and age so then can't accommodate the very slight radial movements made by the shaft, then they leak. Closely compare the edges of the lip where it seals to the shaft and you can often see how it's flattened out a little and if you flex it with your finger you can often feel how it's harder compared to a new one (always a good thing to do when buying new seals as they harden with age too so if you mess about with elderly mechanicals, as I do, you may be supplied with "new" (unused) old stock which then starts leaking almost as soon as it's fitted. The sealing lip should feel quite soft and supple, if it's hard and doesn't deflect easily with your finger I wouldn't buy it.
Makes sense jock! Something else I’ve learned ? thank you for all your help it’s greatly appreciated!
 
Reminds me of a 'clever' mechanic, who installed a drive shaft seal the opposite way around to put the seal lip away from a wear groove. Seemed to leak more than the old one.

I bet you know this PB, but for the benefit of others, lip type seals, especially when used on rotating shafts, often incorporate features which encourage any oil which manages to get past the lip to get "wound" back in. People who work on really old cars will be familiar with "scroll type seals" and this feature is incorporated, in a somewhat different way, in these lip seals. Look at this:

P1090561.JPG

It's actually a Fiat gearbox driveshaft seal and if you look closely you can see the wee angled features which, combined with the rotation of the shaft, encourages the oil back in. Fit this back to front and it will actually encourage oil to leak out. Seals with this feature are "handed" so, for instance, a seal intended to fit the N/S should never be fitted to the O/S - or back to front (ie inside out, if you get my meaning?)
 
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I bet you know this PB, but for the benefit of others, lip type seals, especially when used on rotating shafts, often incorporate features which encourage any oil which manages to get past the lip to get "wound" back in. People who work on really old cars will be familiar with "scroll type seals" and this feature is incorporated, in a somewhat different way, in these lip seals. Look at this:

View attachment 218523

It's actually a Fiat gearbox driveshaft seal and if you look closely you can see the wee angled features which, combined with the rotation of the shaft, encourages the oil back in. Fit this back to front and it will actually encourage oil to leak out. Seals with this feature are "handed" so, for instance, a seal intended to fit the N/S should never be fitted to the O/S - or back to front (ie inside out, if you get my meaning?)
Oh I get you! I always treble check my parts before I buy them and I made sure I paid attention to the seal was situated before I removed it!
I always try take pics as reference before I start and during the job at least then I can cross reference
As I said the seal that came out didn’t in any way look aged but I guess it’s more down to the feel rather than how it looks … unless it’s torn!
 
I bet you know this PB, but for the benefit of others, lip type seals, especially when used on rotating shafts, often incorporate features which encourage any oil which manages to get past the lip to get "wound" back in. People who work on really old cars will be familiar with "scroll type seals" and this feature is incorporated, in a somewhat different way, in these lip seals. Look at this:

View attachment 218523

It's actually a Fiat gearbox driveshaft seal and if you look closely you can see the wee angled features which, combined with the rotation of the shaft, encourages the oil back in. Fit this back to front and it will actually encourage oil to leak out. Seals with this feature are "handed" so, for instance, a seal intended to fit the N/S should never be fitted to the O/S - or back to front (ie inside out, if you get my meaning?)

Lovely explanation Jock, I'm sure appreciated by those who didn't know. That'll be why Fiat fitted different sized seals on the gearbox, to prevent incorrect orientation.
Always good to check the little spring ring is intact inside the seal lip too, I've seen a few with them missing. At least seals tend to come in individual bags these days, seen too many hanging on a string of a label, which can damage the lip.
 
Lovely explanation Jock, I'm sure appreciated by those who didn't know. That'll be why Fiat fitted different sized seals on the gearbox, to prevent incorrect orientation.
Always good to check the little spring ring is intact inside the seal lip too, I've seen a few with them missing. At least seals tend to come in individual bags these days, seen too many hanging on a string of a label, which can damage the lip.
As I've only ever had to do a N/S seal I didn't know about that until a few years ago when I read they were different on our forum - Maybe one of your posts PB? Makes a lot of sense though doesn't it?

Good point too about the little tensioning spring, without it a leak is almost guaranteed and you can damage or displace it during fitting. I'm a bit obsessive with procurement of seals, mostly because there's often quite a bit of work involved in gaining access to change them and I don't want to have to do it twice.

One of my most useful local contacts are these people: https://forth-engineering.com/ who go well above and beyond to try to help. They've obtained obscure bearings and seals for things like my old horticultural machines and even managed to get a primary unit shaft bearing for a DAF variomatic unit I rebuilt maybe 30 years ago which DAF said could not be supplied - recon unit only. They know all about grades of same size bearings and will sometimes suggest a bearing of superior quality to the original fitment. They have no references to the automotive machinery the bearing fits so you either have to take the old part in with you or provide very accurate dimensions. The seals and bearings always come in their own nice little boxes. I've also benefited from the bewildering range of pneumatic fittings they stock. Very good people to know!

I find that between them and these people: https://georgebrown.co.uk/ I can usually tackle anything I'm trying to do.
 
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As I've only ever had to do a N/S seal I didn't know about that until a few years ago when I read they were different on our forum - Maybe one of your posts PB? Makes a lot of sense though doesn't it?

Good point too about the little tensioning spring, without it a leak is almost guaranteed and you can damage or displace it during fitting. I'm a bit obsessive with procurement of seals, mostly because there's often quite a bit of work involved in gaining access to change them and I don't want to have to do it twice.

One of my most useful local contacts are these people: https://forth-engineering.com/ who go well above and beyond to try to help. They've obtained obscure bearings and seals for things like my old horticultural machines and even managed to get a primary unit shaft bearing for a DAF variomatic unit I rebuilt maybe 30 years ago which DAF said could not be supplied - recon unit only. They know all about grades of same size bearings and will sometimes suggest a bearing of superior quality to the original fitment. They have no references to the automotive machinery the bearing fits so you either have to take the old part in with you or provide very accurate dimensions. The seals and bearings always come in their own nice little boxes. I've also benefited from the bewildering range of pneumatic fittings they stock. Very good people to know!

I find that between them and these people: https://georgebrown.co.uk/ I can usually tackle anything I'm trying to do.
Got my new axl bolt but how do you lock it once torqued ? Do you split it while it’s on or before!?

Sorted! I think I’m tired ? nut secured phew!
 
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Baglady:
I refer to them as Hub Nuts. Axle bolt is fine :)
Only stake the fixing once final torque has been applied, typically with the wheels on the ground. A previous poster mentioned "barb" and I agree, if possible try and make it resist the unwinding action.
However, overall, I've not known any fasteners come undone when they're tightened to these extreme high torque values. I work on trains and see 1500Nm for some bolts (two people holding the massive spanner etc) but the spec still says put in a split pin or such!
 
Baglady:
I refer to them as Hub Nuts. Axle bolt is fine :)
Only stake the fixing once final torque has been applied, typically with the wheels on the ground. A previous poster mentioned "barb" and I agree, if possible try and make it resist the unwinding action.
However, overall, I've not known any fasteners come undone when they're tightened to these extreme high torque values. I work on trains and see 1500Nm for some bolts (two people holding the massive spanner etc) but the spec still says put in a split pin or such!
I got there in the end I guess by just paying attention ? I checked my drivers side and then it sunk in! On the upside (or down) I’ve developed quite muscular arms due to torquing ?? think Linda Hamilton T2 I’ve done a lot of muscular work on my car this year like suspension ..brakes .. and the rest!
 
On the subject of driveshaft oil seals I recently had the Twinair serviced (basic, it's only done 1200mls since November 2020) and the mechanic reported the seals were weeping a little oil. Not enough to actually drip apparently. Could you knowledgable folk advise; can this be left to the next service, which may be another twelve months bearing in mind my low use or should I have it attended to as a matter of urgency?
 
My attitude towards seals is that if they are only making their surrounding area "moist" I tend to just leave them alone and keep an eye on them. The one exception being if I have a car with a timing belt where the oil might contaminate the belt then I'd attend to it immediately. Something like a driveshaft seal weeping a little I could live with for a long time. My boy's Punto was leaking oil from it's gearchange quite badly - It was leaving a small grubby patch on his driveway - so we changed it. Our own Panda has the same leak but is not yet actually dripping so I'm just keeping an eye on the oil level in the gearbox. It's been like this for over 2 years now and I'm not loosing any sleep over it! If they didn't check the oil level in your 'box (and probably on a "small" service they wouldn't have?) it might be prudent to just pull the level plug and have a wee look?
 
My attitude towards seals is that if they are only making their surrounding area "moist" I tend to just leave them alone and keep an eye on them. The one exception being if I have a car with a timing belt where the oil might contaminate the belt then I'd attend to it immediately. Something like a driveshaft seal weeping a little I could live with for a long time. My boy's Punto was leaking oil from it's gearchange quite badly - It was leaving a small grubby patch on his driveway - so we changed it. Our own Panda has the same leak but is not yet actually dripping so I'm just keeping an eye on the oil level in the gearbox. It's been like this for over 2 years now and I'm not loosing any sleep over it! If they didn't check the oil level in your 'box (and probably on a "small" service they wouldn't have?) it might be prudent to just pull the level plug and have a wee look?
Many thanks for your sage advice(y)
 
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