TCS axle bearing

[GavinT]

I see there is a dust seal on the inside at the u-joint but not on the outside bearing? What other than the bearing seal seals the outside bearing?

If I recall, the original inner 6006/31 bearings weren't available as 2xRS, so Lotus made provision for the separate inner seal.
I think the outer 6206 was commonly available with two seals.

Someone please check my recollection on this.

[jbcollier]

The first Europas came without the extra seal on the driveshaft side.  It was added due to longevity concerns about the inner wheel bearing.  There isn’t an extra seal on the outer side as that is shielded by the brake back plate and the drum.

[TurboFource]

Gavin,
Perhaps the unsprung grease is an "unsprung hero" 🙄

[Dilkris]

There isn’t an extra seal on the outer side as that is shielded by the brake back plate and the drum.

Correct me if I am wrong but there cannot be a seal on the outer side as it is the outer race of this bearing (secured firmly between the hub and trailing arm) that effectively locates the stub axle in the hub. (I remember you highlighting this fact in a previous post some time back when I was trying to get my "head around" exactly how the rear hub/bearing/hardened spacer arrangement works. For me it has to be one of the most short sighted engineering designs on the car - I note on the much later Eclat/Elite, with very similar rear suspension arrangement, Chapman saw fit to change the bearing set up. Chris

[jbcollier]

+1 that the rear axle is woefully over-taxed.  It was fine for the 40hp Imp it came from.  The Imp rear axle was widely used in period formula cars and it was a problem there as well.

If you wanted, you could engineer in an outer seal.  Have an extension on the backplate to house the seal and machine down the hub for it to run against.  It's just not a problem though.

[GavinT]

Gavin,
Perhaps the unsprung grease is an "unsprung hero" 🙄

Haha . .
I guess I asked for that.

OK, seriously, then . . if corrosion is of concern then perhaps a shot of Boeshield T-9 and a cork in the lower hole would suffice?

[GavinT]

+1 that the rear axle is woefully over-taxed.  It was fine for the 40hp Imp it came from.  The Imp rear axle was widely used in period formula cars and it was a problem there as well.

And in the Europa design there's that 3/8 inch spacer behind the hub too.
That translates to 3/8 inch less spline engagement than even the Imp!

[SwiftDB4]

+1 that the rear axle is woefully over-taxed.  It was fine for the 40hp Imp it came from.  The Imp rear axle was widely used in period formula cars and it was a problem there as well.

And in the Europa design there's that 3/8 inch spacer behind the hub too.
That translates to 3/8 inch less spline engagement than even the Imp!

And the splines extend underneath part of the outer bearing which causes a big wear problem. Why didn't Lotus change some of this? Why can't newly manufactured axles change this? The Imp went out of production in 1976.

[jbcollier]

For a race car that has its bearings and axles replaced frequently, it is a brilliant, inexpensive set-up compared to what was in the 47.  For a road car?  Not so much.  There are several redesigned set-ups out there with the common denominator of not being cheap.  If you have a good machine shop, there is the Corvair/Corvette rear axle set-up as well.  Though what you save in parts cost is probably more than eaten up by machining costs.