So bottom line is that the seals are correct for the bearings and do in fact offer protection?
The thread never really came to a conclusion but, from my understanding SPF did research the seals issue and feels they are adequate protection.
I'm an electrical not mechanical engineer but the principle of the seals seems sound (and very clever) to me (wear a groove in the outer race and allow grease to migrate into it to serve as a seal). No doubt it is not as long-lasting nor as strong a barrier to water/dirt ingress as a typical spring loaded lip bearing, but they take up little space, required no pressing or prying, and the seal (grease) is renewable in a way that is consistent with race/exotic car maintenance.
As for SPF's research and feelings... How would I know? I'm only a customer... :stunned:
But at a minimum this is the way GT40s were built in the first place so they are definitely "correct."
OTOH, the seals are relaively fragile and their sealing action could be compromised or destroyed by any ham-fistedness on the part of a mechanic (or factory assembler). Richard's show signs of having been ham-fisted (oh, that is an unfortunate verb) at the factory.
Anyway, for what it's worth, I think they're quite elegant as a mechanical problem solution but I think anyone who is maintaining a GT40 needs to be aware of them and their foibles. My intuition is that the hubs should be disassembled at worst annually to clean and restore the grease seal, otherwise the seal will disappear on its own and allow dirt in as well as the natural temperature-driven breathing action of the hub will allow water to collect and eventually wear and corrode the bearings.
And as usual, if it weren't for this forum (and for Carroll Smith, RIP) I would never have known, and had I been so unlucky as to have taken my hubs apart for some reason and NOT known what those things were I probably would have treated them as "dust shields" and possibly would have ruined them.
And that pretty much sucks, but I'm not going to beat the documentation dead horse any further, because I suspect it's a waste of energy. You know, don't try to teach a pig to sing and all that....
That's just my opinion. I'd like to hear from the mechanical illuminati in the crowd.