Rebeldryver's '65 Impala SS Black Betty

[Scott Liggett]

The grainy flaky section is brittle overload failure where it snapped off. The smoothish flat section with stripes looks like a fatigue crack growth pattern known as "beaching marks" as the crack gets bigger and bigger under load cycling. No ideas why it happened but that is what looking at it through a picture says to me.

Would I be able to see these beaching marks before it snaps?

[CTX-SLPR]

If you did penetrant testing on the spindle (or mag particle, "magnaflux") you'd be able to see the crack that they are formed in. The beaching marks are inside the crack and you really only see them after it comes unzipped. Knowing what they are more tells you how it failed (over time vs. overload) than it is a method of catching them. Radiography (X-ray) would stand a chance to see the crack with some good setup and a load on the spindle tip to pull the crack open some.

No garantees but you can do simple penetrant testing with some light oil and chalk dust. Clean the crap out of the area without scratching it up (if you use solvents, heat it up to get it out of any cracks), spread the oil on the part evenly and let it sit for an hour or so. Clean the oil off with a dry cloth, no solvent, then sprinkle chalk dust on the whole inspection area evenly. If there is oil soaked into a crack it will come out into the chalk dust. Google "Oil and Whiting Inspection" to see what I'm talking about.

[Deaf Bob]

Wow! I forgot about that chalk trick....
Even old dogs can relearn stuff!

[DanStokes]

We did that in school (WAY back) but I haven't thought about it since. Good reminder. We had Magnaflux, Zyglo and others but they taught us as many methods as they could think of knowing that a shop that hired one of us might have any of the above. I agree - great reminder.

Remember, this has been nearly 50 years ago......

Dan

[Huskinhano]

I heard about the chalk test too and to be honest I forgot all about it. It would be interesting to find the cause of failure. It could have been some little thing someone did 25 years ago, like chisel off a bearing and knocked the axle.

When I work at Hertz world headquarters we had one of the hydraulic elevators fail. It was leaking oil into the ground. The pit would up. It was quite interesting how they replaced the hydraulic cylinder. Cut to the chase, the outside of the cylinder has an epoxy coating to prevent it from rusting in the ground. The cylinder's coating looked great, it was a out 16 years d.On the very bottom it failed and rotted through. The spot where it failed looked exactly like someone used a utility box cutter to cut off a sticker. There was this perfect rectangle about 1" X 2" The angles and sides were sharp and true. Outside of that area the coating was perfect. I always wondered if that is what happened.

[Scott Liggett]

Chisel marks would show up very clearly. I am not too worried about it.

[Huskinhano]

Chisel marks would show up very clearly. I am not too worried about it.

Didn't mean exactly like a chisel but maybe some event by a PO. Or maybe just a fault of the material. it would be interesting to know the cause. Any luck with a replacement spindle?

[Scott Liggett]

I showed the broken spindle to our quality control manager this morning. He put it under the neato camera microscope thing-a-ma-bob. He said the shiny smooth areas showed it was cracked and rubbing for a while, the shiny smooth areas. The rough area is where it finally broke. Why it started cracking from stress is a mystery. It has had 50 years of driving on it, the last 18 in my hands.

[Huskinhano]

Curious, since it was flexing a little causing the rubbing, did it feel any different? A guy on the Mustang forum had a 4 link on his rear axle and kept getting wheel hop he couldn't get rid of. One day he took it to his friend's shop just for a front end alignment. I guess they were doing a 4 wheel alignment and immediately noticed something wasn't right. The rear axle was warped from welding and the axle was so warped it had 3/4" toe in! He said he was probably too aggressive when he welded the brackets on. He's getting a new axle from Currie. Yes, the tires were feathering.

[DanStokes]

Curious, since it was flexing a little causing the rubbing, did it feel any different? A guy on the Mustang forum had a 4 link on his rear axle and kept getting wheel hop he couldn't get rid of. One day he took it to his friend's shop just for a front end alignment. I guess they were doing a 4 wheel alignment and immediately noticed something wasn't right. The rear axle was warped from welding and the axle was so warped it had 3/4" toe in! He said he was probably too aggressive when he welded the brackets on. He's getting a new axle from Currie. Yes, the tires were feathering.

It's surprising how much the axle shafts will bend w/o breaking and how long they'll live like that. Kinda like a '63 Tempest driveshaft.

Dan

[Shelty]

It's surprising how much the axle shafts will bend w/o breaking and how long they'll live like that. Kinda like a '63 Tempest driveshaft.

Dan

the old rope driveshaft?

[Scott Liggett]

Curious, since it was flexing a little causing the rubbing, did it feel any different? A guy on the Mustang forum had a 4 link on his rear axle and kept getting wheel hop he couldn't get rid of. One day he took it to his friend's shop just for a front end alignment. I guess they were doing a 4 wheel alignment and immediately noticed something wasn't right. The rear axle was warped from welding and the axle was so warped it had 3/4" toe in! He said he was probably too aggressive when he welded the brackets on. He's getting a new axle from Currie. Yes, the tires were feathering.

It had some wandering on rutted roads, but that could've been from the massive front tires and non stock alignment.

I hit an island with the left rear tire in my '73 Impala causing me to spin in a 180* into a bus bench. It bent the rear diff housing to be toed out 1/2". The alignment shop thought I was crazy I wanted a 4 wheel alignment to see how bad it was.

[Deaf Bob]

the old rope driveshaft?

Probably torque shaft to transaxle..

[malc]

I showed the broken spindle to our quality control manager this morning. He put it under the neato camera microscope thing-a-ma-bob. He said the shiny smooth areas showed it was cracked and rubbing for a while, the shiny smooth areas. The rough area is where it finally broke. Why it started cracking from stress is a mystery. It has had 50 years of driving on it, the last 18 in my hands.

Right there....

[Scott Liggett]

I haven't done much lately to the car because money has been short lately.

I finally got the new spindle brackets and new inner bearings and seals. They looked fine, but I decided to to replace them anyways. The outer bearings just got repacked.

The nice thing about this era of Impalas is that it is super easy to replace the spindles. You don't need to remove the strut rods or sway bar links. Just knock the ball joints loose and you are set. The coil spring doesn't move.


The new spindle in. Takes about 15 minutes.



The old driver's side spindle looked fine. I can't see any cracks at all. I smacked it a few times with a hammer just for fun. Nothing.



The new spindle brackets are anodized black instead of zinc washed.


All back together.