Diff output bearings.

[davidj]

Good afternoon.

As the body is off my 1966 s3, I am changing the diff and rear wheel bearings. I have Issue 16 rear
uprights so am about to purchase 4 x 6206-2RS which have rubber seals. I still have the diff bearings I removed from my 1970 +2 (I never throw anything away!) and they have metal shields and skf number 412419 . I was told by a bearing supplier the modern skf equivalent for this is 6206-2Z. I guess the 2Z signifies metal shields while 2RS rubber seals. However, while I have not yet removed the bearings from the s3 diff, they look to have rubber seals.

So the question is should the bearings in the diff have rubber or metal shields or does it matter?

Thanks in advance!

Cheers,

David

[StressCraxx]

2RS is what you want. The metal shields (2Z or ZZ) have a clearance to the inner race. So, dirt and moisture can enter easily. The rubber seals actually contact the race and provide a static and running seal, like the lipseals on the crankshaft in the engine.

I used to work for SKF.

Regards,
Dan

[Davidb]

Also, make sure that the rubber lip seals are mounted inboard of these bearings. My car came to me without them and there is no evidence they were ever fitted!

[davidj]

Thanks for your reply. I agree that rubber seals would be the obvious option. However, it raises another question: why was my +2 diff fitted with metal shields, and the replacements (I think from Matty) also had shields?

Any suggestions anyone?

Thanks,

David

[denicholls2]

There are two obvious possibilities:

1. How many times can a model year determine with certainty what equipment was originally used in a Lotus?
2. They might have been replaced before using the non-original materials. You have the opportunity to do this now and are contemplating it; are you certain someone before you in the 50-year lifespan of the car did not?

[davidj]

Good points, but the only reason I considered using the bearings with metal shields was because that was what Paul Matty supplies!

[rgh0]

There are two bearing part numbers shown in my parts manual 036D6001 and 036D6017. The drawing actually shows a bearing with a rubber O ring seal on the external race ? Maybe early on there was no inner seal and Lotus relied on the bearing to also act as the seal ? Until they discovered it leaked to much Maybe at some stage Lotus used shielded bearings for some reason like they were cheaper

Confusion and lack of understanding of previous owners and suppliers on what is the correct bearing specification will also add to the mix of whats in diffs and what is supplied.

I would stick to a 6206-2RS bearing

cheers
Rohan

[Davidb]

Yes, I agree with Rohan. I realise that my comment earlier could be misinterpreted. My car had no inner seals fitted in the diff and there was no evidence that any had ever been fitted! Consequently I had leaks from both sides as I reported here a while ago. I first polished the seal bearing surface on the shafts and then fitted lip seals-no leaks now and yes, I used 6206 2RS bearings.

[2cams70]

One of the bearings (not the 6206 one) looks to be just a standard Ford Escort rear wheel bearing. It's used on many cars with live rear axles - eg. Gemini, Toyota, Hillman, etc. not just Ford Escort. It's shielded on one side and has a contact seal on the other. In the Escort application the contact seal prevents rear axle lubricant from entering the bearing. Similarly the "O" ring on the outer race is there to prevent rear axle lubricant from escaping around from around the outside of the bearing.

Or it could be Anglia or Cortina. The Anglia and Cortina bearings are a little narrower. I know the Anglia (unlike the Escort which depends solely on the bearing for rear axle oil sealing) has a separate leather seal inside the axle tube just prior to the bearing. So depending on the exact dimensions the Elan bearing could be Anglia / Cortina or Escort. Definitely appears to be one of these however. They may have changed also depending on year.