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-   -   HydroStick failure (https://forums.maxperformanceinc.com/forums/showthread.php?t=829813)

Jack Gifford 05-20-2019 01:04 AM

HydroStick failure
 
After five years of good service the front clutch quit working in the HydroStick of my '59 GMC (no 2nd or 4th gear). I got it out and apart and the front ring land of the oil delivery sleeve is collapsed, preventing sealing to the front hub. The steel thrust washer had "chewed" the face of the delivery sleeve, but I don't know why. Fixing it is a simple matter of replacing the sleeve and washer, but my concern is understanding why it happened. Also, the anti-rotation tang of the washer is chewed away. Anybody ever have such a failure of a DualRange Hydramatic?

Jack Gifford 05-21-2019 02:17 AM

When I first discovered the worn-away tang of the steel washer, I thought that might explain the damage to the sleeve. But on second thought- the tang would keep the washer rotating with the intermediate shaft (usually near engine speed). Huh? It would make more sense to me if it were designed to be anti-rotation to the sleeve, so that relative motion would be between the steel washer and the bronze washer in front of it? So I'm faced with two puzzles- why this design:confused:, and why did it fail.:confused:

389 07-11-2019 07:01 PM

We have a local here named Sweeny who builds those. My buddy has one behind a 50s Caddy motor in a 40 Ford..

Jack Gifford 07-12-2019 02:38 AM

Where's "here"?

stevep 07-12-2019 07:48 PM

I have been doing those units for 30+ years and I have never seen that happen...unless you have an end play issue

Jack Gifford 07-15-2019 12:55 AM

stevep- Can you tell me why the steel washer at the front of the delivery sleeve is "tanged" to the intermediate shaft instead of being [somehow] fixed to the delivery sleeve?

mgarblik 07-16-2019 09:49 PM

Jack, do you have an exploded view of that assembly? I know little about those transmissions, but if something doesn't make sense to you I wonder if it was assembled incorrectly 5 years ago and just ran that way until it failed?

Jack Gifford 07-17-2019 02:04 AM

Whatever the explanation, I'm the only one to blame. And yes, anything's possible- I got the endplay wrong, face of the sleeve wasn't perfectly flat, or a dozen other things. Until this failure, I hadn't given much thought to the design of this area. But studying it now I'm puzzled about why two steel surfaces are constantly running against each other at near engine speed. Other similar areas of the hydro typically use bronze-against-steel. That's the first part of the puzzle. The second part is- why does this design usually work fine, but failed this one time.
There's little chance of finding someone to shed light on this, so I'll probably have no choice but to replace the parts and cross my fingers. But... god, how I hate pulling/replacing this thing...:eek:

mgarblik 07-17-2019 10:36 PM

Agree, steel running on steel doesn't seem normal. Again, no personal experience with this trans, but any chance one of the steel pieces originally had a bronze facing that has worn off due to lack of end play or if only one side had a bronze facing was installed backwards? I guess when you get the new parts, that may answer those questions. Good luck with it.

Jack Gifford 08-10-2019 02:46 AM

2 Attachment(s)
The failure is still puzzling, but I've ordered new pieces (delivery sleeve, etc.). I'll carefully re-assemble it, paying extra attention to end-play of everything- and cross my fingers!
In the meantime, I spent a few hours trying to make installation of the transmission more user-friendly. I always have trouble keeping the torus cover gasket in place while raising the transmission up into the bellhousing- the input shaft usually bumps the gasket and moves it out of place (can't let sealer set up to hold the gasket, as it needs to remain soft while bolting the torus cover to the flywheel). So I grooved the cover for .103" square O-ring stock (Buna-N). Fixturing the cover true to within +/- .002" was time-consuming, repetetively shimming/clamping/checking. Although the offset boring head bar is 3/4" diameter, vibration was a problem, thus the lead weight bolted to the bar. Very small slow cuts were required, but the result is good. The stock protrudes nominally .030" from the cover face, no sealer will be required.

Jack Gifford 08-11-2019 01:45 AM

[Sorry I misspelled 'repetitively']

Jack Gifford 08-17-2019 01:42 AM

Finally- all is explained. Regarding the puzzling question about the steel washer chewing up the delivery sleeve- they aren't intended to ever touch each other! A broken thrust washer near the rear of the transmission allowed the intermediate shaft to move back too far, causing the steel washer to collide with the delivery sleeve. And it appears that I'm to blame for the broken thrust washer, by apparently not accurately checking endplay when I last refreshed the transmission. Substituting a new .075" washer for the broken .085" one gives .013" play (in an allowable range of .007"-.015"). So it must have only had .003" play- oops! But having now explained it all, I can happily replace pieces and get it back into service.:)


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