BB-7063, 4-speed pilot bearing spacer

AA Ford Discussion Group relating to the repair and restoration of your AA Ford.
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Posts: 77
Joined: September 30th, 2009, 8:02 pm
Body Type: none
Model Year: 1930
Location: Massachusetts

BB-7063, 4-speed pilot bearing spacer

Post by vonheine » November 5th, 2018, 7:41 pm

I am hoping that the club's 4-speed overhaul expert or historian can explain to me why Ford made this particular spacer out of round wire instead of as a machined part with a cross-section that has parallel surfaces or as a "D" shaped spacer made from slightly harder material or perhaps bearing bronze.

I have searched for a NOS BB-7063 for a long time without success. I have disassembled three 4-speed transmissions and all three are worn and have flat spots on one side which changes the original round cross-section into more of a "D" shaped cross-section. More importantly, this reduces the amount of spacing by the amount of lost material. A worn spacer changes the relationship between the BB-7017 Main drive gear, BB-7120 pilot bearing, and the BB-7061 Main shaft, and may lead to the transmission popping out of 4th gear under a load.

I could machine new spacers from scratch with either parallel faces or as a "D" shape with original thickness from the flat to the far side of the round. All of the wear is always on only one face, so why can't I just make a new spacer to original thickness with a "D" shaped cross section and place the round face as the wear surface? Has anyone ever done this? Is there a Ford engineering reason why the spacer must be round on both faces? Do you think Ford made it round like a "bull ring" just for cost reasons, or is the round cross-section key to lubrication flow and reduced contact area? Could both faces be parallel? An original Ford BB-7063 measures: OD=1.100, ID=.8125. wire diameter is .144

Bob C
Posts: 1321
Joined: April 24th, 2003, 11:50 am
Body Type: Mail truck, Stake tr
Model Year: 1931
Location: SO CAL

Re: BB-7063, 4-speed pilot bearing spacer

Post by Bob C » November 6th, 2018, 1:36 pm

You might check with VanPelt sales, they show it. ... 4speed.htm
Mac is great to deal with.


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