1951 Pontiac Chieftain

[PhilA]

Looks like the ring dug in and spun the sleeve and broke up the drum and sleeve.

My concern now is the valve block- the fluid dumps out the way it went in, and that'll have been drawing a lot of swarf through.

Phil

[PhilA]

Ok. Pulled the other drum off the shaft.
Root cause: centralizing bearings failed.

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This allowed the drum to sit at the wrong angle and wear on the fluid delivery sleeve, shredding it and melting it slightly.

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Fluid delivery sleeve is banjaxed. The additional heat appears to have fractured the ring which caused the secondary bushing to wear more and allow the other drum to misalign.

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The shaft however appears to have survived relatively unscathed. That would explain why it smelled so horrible when I pulled the main cap bolts.

So:
Front drum
Rear drum
Fluid delivery sleeve and associated bushings and rings

That should solve that part. Haven't pulled the valve block apart yet.

Phil

[PhilA]

Parts are available in New Jersey.

Need to take one drum apart to count the sun teeth because there's a couple ratios they used and the gear isn't marked externally as to which is fitted, you gotta count the teeth.

Phil

[PhilA]

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Oh dear. That's all burned up.

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And that's pretty unhappy looking, too.

Phil

[Junkman]

The inevitable consequence when a band is too lose.
But the discs and plates should come in the master rebuild kit, no?

[PhilA]

Yes, I'm going to get the drums, center section, have all the seals, gonna but a full set of frictions and steels.

The outer band land is a bit worn in a couple of concentric lines but it's otherwise smooth. It'll have to do. It does grip nicely when tightened up just by pressing on it.

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The friction discs still have material on in the secondary and the steels are still smooth but have heat fractures beginning to radiate out so I'm going to replace them. False economy not to.

Phil

[PhilA]

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My snap ring pliers arrived.

Phil

[Junkman]

When it comes to tools and equipment, you just can't beat the septics.

[Eddie Honda]

But you can.

[PhilA]

Spent last night taking measurements of the thrust washers and doing some calculation.

The main shaft end-float is a compound of all the thrust washers and machine faces between the main center bearing and the back of the gearbox, so 4 washers and a shim.
When the gearbox was still all in one piece I measured the lash and it is 0.019", which is just outside of the 0.004-0.018" specification.
The thrust washers are quite worn. One is all the way through the copper coating, and regardless needs replacement. They measure 0.087" and 0.088" respectively, new they are 0.090" so I just ordered 2 new standard thickness ones and a slightly thicker main shaft end-float washer to bring me back into spec.

--Phil