Well, here’s a thinker – or maybe not.
I pulled the rear end on the Midget a few weeks ago, pulled the hubs and replaced the wheel studs with some longer units from a Mini Cooper. All’s well, reinstalled the axles – the splines looked great – and I hand turned the pinion. It turned freely, but every complete turn of the crown gear, there was a spot where it was just a touch tougher to turn – barely perceptible, not grinding or anything that created a noise, just a small bit of extra resistance.
As I’m at the point where I’m trying to reduce every possible Newton of resistance, I reluctantly pulled the pumpkin.

The crown gear and the pinion looked flawless. The pumpkin came out of a 1959 Bugeye, and the gears have clearly been harmoniously working together since Harold Macmillan lived at 10 Downing Street. These things were notorious for slap-dash assembly and disinterested inspection, but were also designed so that they never really had to be put together all that carefully. On Spridgets, the axles tend to go before the diffs. I saw no unusual wear patterns, to the naked eye everything looks great, and if it were in a street car, I’d just throw it back in and go.
But taking the dial indicator to it showed it just far enough out that I may have to do something with it.
The backface of the crown gear varied .0035 through a complete rotation – the tight spot, right where I felt the nominal resistance. It’s likely that some of that is just take-up onto the bearing shims. The circumfrance runout was also .0035, corresponding to the tight spot. The pinion turns freely with no funny business or slop.
Lash was .010. Factory spec is .002, but given the great shape of the gears and that I’m trying to lose some rolling resistance, I’m not uncomfortable running that a little loose. Bearings all looked good.
What I plan to do is simply remove the crown gear, clean everything up really well and reassemble it, hoping to better index the crown gear onto the differential cage.
And speaking of pumpkins –
Kate reminded me yesterday that Trick or Treat was this afternoon in our neighborhood, and that she needed help cutting Jack-O-Lanterns. I told her I was already working on a pumpkin, but she didn’t appreciate the joke.
Kate took hours, painstakingly drawing the face and carving her gourd.
I had mine done in 5 minutes . . .

