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Lip seal failure

PostPosted: Wed Mar 28, 2018 1:39 pm
by jono
I've just pulled and split my diff after only 2k miles due to a leaking offside output shaft seal.

I used SKF bearings and new lip seals (though of uknown origin). All were carefully fitted and I used a little Wellseal in the seal housing. I also lubed the lip seal with redline assembly lube

Can anyone say why the seal failed in a short time? This time I've obtained SKF lips seals and new SKF bearings and hope this will solve matters.

I did use the wrong oil - EP90 GL5, could this have had an effect on the seal or could it simpky be the case that I have bought unbranded, crap seals, of uknown quality?

Is there a particular finish you require on the metal shaft - should I hone it slightly with some fine wet and dry?

PS: re filling with GL4 this time! (there's a slightly glittery hue to the old oil :shock: )

Re: Lip seal failure

PostPosted: Wed Mar 28, 2018 2:31 pm
by JonB
Hi Jono

I recently changed my pinion seal. I'd bought it from Miles Wilkins when I visited him late last year. Haven't had any leakage yet. I refilled with GL4 EP90 and smeared a little round the seal (as well as put Wellseal in the splines and pinion nut as Miles recommended).

Maybe you have been unlucky with your seals. I can't think of any other reason for you to encounter problems.

By the way, the rubber used in my seal is sort of olive green coloured, if that helps. I bought a pair of output shaft seals, too, but never fitted them as I couldn't get the shafts to come out and there was no leakage.

Re: Lip seal failure

PostPosted: Wed Mar 28, 2018 2:40 pm
by jono
Hi Jon,

Yep, did the pinion seal at the last time and that's never leaked a drop (and didn't Wellseal the splines), only the drivers side output seal. Crap seals I reckon so SKF everything this time

(top tip: heat casing and use and old driveshaft with bolts as a slide hammer to pull the output shafts)

Re: Lip seal failure

PostPosted: Wed Mar 28, 2018 3:47 pm
by JonB
I knew that :D Problem was I was trying to use a home made slide hammer and chains. Not enough shock impact to pull the bearings out. I think they can be done without taking the diff out, so if there is leakage I'll buy a slide hammer and have at it again!

Re: Lip seal failure

PostPosted: Wed Mar 28, 2018 4:13 pm
by promotor
jono wrote:I've just pulled and split my diff after only 2k miles due to a leaking offside output shaft seal.

I used SKF bearings and new lip seals (though of uknown origin). All were carefully fitted and I used a little Wellseal in the seal housing. I also lubed the lip seal with redline assembly lube

Can anyone say why the seal failed in a short time? This time I've obtained SKF lips seals and new SKF bearings and hope this will solve matters.

I did use the wrong oil - EP90 GL5, could this have had an effect on the seal or could it simpky be the case that I have bought unbranded, crap seals, of uknown quality?

Is there a particular finish you require on the metal shaft - should I hone it slightly with some fine wet and dry?

PS: re filling with GL4 this time! (there's a slightly glittery hue to the old oil :shock: )


EP90 GL5 the incorrect oil? Not in my book! GL4 only when used in gearboxes with brass synchros. GL5 for hypoid gears (ie diffs). The only time you might have to use GL4 oil is when used in a transaxle etc where the synchro rings and differential gears share oil.

Where did you get this info from?

Regarding the seal did you lube it before fitting the driveshaft? They need a bit of lube on them to help with first time running.
The original Lotus fitment seals are branded "GACO" seals.

Re: Lip seal failure

PostPosted: Thu Mar 29, 2018 3:54 pm
by jono
Promotor,

My misunderstanding; you are quite correct about the GL5 spec in the diff. Looking back at my car file that's what I've used on the last two occassions and I must have got confused about the GL4 when I observed a distinct gold metallic flek in the diif oil when I split the casing put two and two together and concluded that I'd used the wrong oil.

I've had the oil swapped to GL5 now so will use this when I put the diff back in.

I used Redline assembly lube on the new seals when fitting them last time - the new SKF seals have arrived and they look much better quality than the ones I used last time and they have a double lip on them. We'll see how it goes.

The GACO seals (George Angus & Co) used to be made in my home city of Newcastle however, alas, the name appears to have been bought and they are probably made in China now

Re: Lip seal failure

PostPosted: Thu Mar 29, 2018 4:08 pm
by Hawksfield
Hi
my-puller-a-better-use-of-drive-shafts.jpg and

My slide hammer


Recently fitted new seals without problems, did not coat with oil just filled with oil (GL5 EP90) on the bench and hand turned to circulate the oil no leaks.

Re: Lip seal failure

PostPosted: Thu Mar 29, 2018 4:50 pm
by jono
Hi John,

That's exactly how I removed mine, plus a little heat, and they were fixed with Loctite 660.

Jon

Re: Lip seal failure

PostPosted: Fri Mar 30, 2018 9:02 am
by gjz30075
Make sure the diff breather is clear and not plugged. Excess pressure inside could blow the seal.

Re: Lip seal failure

PostPosted: Fri Mar 30, 2018 2:21 pm
by promotor
jono wrote:Promotor,

My misunderstanding; you are quite correct about the GL5 spec in the diff. Looking back at my car file that's what I've used on the last two occassions and I must have got confused about the GL4 when I observed a distinct gold metallic flek in the diif oil when I split the casing put two and two together and concluded that I'd used the wrong oil.

I've had the oil swapped to GL5 now so will use this when I put the diff back in.

I used Redline assembly lube on the new seals when fitting them last time - the new SKF seals have arrived and they look much better quality than the ones I used last time and they have a double lip on them. We'll see how it goes.

The GACO seals (George Angus & Co) used to be made in my home city of Newcastle however, alas, the name appears to have been bought and they are probably made in China now


"Gold flecks" could be early planet and sun gear thrust washers when viewed through oil - early diff centres used a copper type overlay material for the thrust washers.