Thanks for the advice.
Things I checked:
it was 30 degrees in the shop. Same as when I drove the car and had the death wobble.
1. Toe-in was done using the Les Andrews string method 4 months ago.
Rechecked and still in spec.
2. Tire inflation good at 32 psi.
3. All drag link & tie rod spring and cups had been overhauled in 2023 with the nylon variation. All tight, I considered tightening them if I did not find a problem.
4. All balls on spindles, pitman arms, etc. still round to 0.002"
5. Pitman arm and sector housing tight.
6. King pin bushings, King Pins, KP thrust bearings all tight. Checked with reamer and and still snug. see pic
7. Backing plates without play.
8. Wishbone tight and wishbone's ball re-greased and snug in clamp.
9. Shocks rebuilt in 2021. Still dampen well.
10. 1 1/2" play in steering unchanged in last 2 years.
11. Essentially everything was tight, adjusted, in spec, or approprate except...
12. Axel bearings ------ BOOM
The Problem
When I pulled the rims off to check everything from the Kingpins to the spindles, there was some play. Up-down, side-to-side, and on the diagonal. Basically, the hub and drum wobbled in all directions, albeit just a little bit. The backing plate and kingpin did not move. The axle did not move. So, I re-tightened the axle nut per Les Andrews instructions/procedure. No change.
I pulled the hubs off and EUREKA the races of the outboard bearing were so loose I could turn them in the hubs with my fingers. The last time I drove the car with out the wobble was late Autumn, 65 degrees or warmer, and the Summer. The day of the death wobble and this inspection it was 30 degrees. At that temp metal shrinks.
The Driver's side is worse than the Passenger's side. But, both races turn in the hubs. The bearings and the axle are in great shape. Plenty of grease, no wear or rust, or damage.
The Solution
Our club all discussed this over brain-juice, aka coffee. We came up with three fixes. The members were split essentially down the middle. The grey-hairs went one way the non-greys went a different way. The mechanics went the modification way and the intellectuals went the accessory way. Both groups nodded acknowledgment to the other's solution. And both stated, "we are often wrong, but never in doubt."
1. Use a long center punch and ping divots into the inside of the
hub where the races seat. Punch 15-20 divots all the way around.
Consider a second row. Coat the outside of the race with JB Weld
or Permetex's Seating Compound and re -press the races in. Wipe
off the excess carefully. Let it sit for more than 24 hours and
reassemble. The theory is the hubs are dead anyway.
Contracted in the cold, they shrank and released the races. The
divots raise metal to fill the gap and allow the races to reseat and
the 'glue' fills the gaps and prevents loosening in future. The 'red
wrench' would allow the glue to release if I wanted to remove the
races. You cannot kill a dead horse by flogging it.
2. Measure the gap and use brass shim stock. Make a circumferential
brass shim and repress the races in. This group claims a better
solution because the shim stock, being equidistant in the
thickness will keep the race and consequently the hub centered
on the axle and the divots may all be different heights. Make
sure the shim is appropriate thickness.
3. Wait till it warms up and the hubs will expand and let the races seat
again so there is no play for them to wobble. Drive it in on the
hot days only with the windows down and windscreen open.
Does anyone have a vote for which solution is best?
Thanks,
Diastole in the Smokies
