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| | | | Joined: Sep 2020 Posts: 3 Moderated | | Moderated Joined: Sep 2020 Posts: 3 | Hi folks, so as the title states I have a 48 Chevy 3100 with a 4 speed SM trans. Ive replaces the u joint and new gaskets for the universal ball. I have fully tightened the rear seal retaining cup , drive the truck a short distance and find the cap loose again. Any thoughts would be appreciated as this truck is fairly new to me.
Jon | | | | | Joined: Feb 2019 Posts: 4,507 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,507 | I replaced mine back in Dec. of last year and have tighten the collar a few times also. In my case, I don’t believe that the collar is backing off, but the packing is wearing in (as I drive) causing the collar to appear loose. My thoughts are it’s just wearing in and will eventually seal.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | | | | Joined: Feb 2004 Posts: 29,871 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,871 | Seals can only stay put if the shaft they're running on is stable. You probably need to replace the ball bearing in front of the seal.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2009 Posts: 554 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 554 | I use 2 hose clamps with a short piece of flat aluminum between them to keep that rear collar tight. One clamp on the collar, the other on the shaft. The flat aluminum piece clamped between them keeps the collar from rotating. I believe Phak1 is correct about the cork packing wearing in. My collar continued loosing after a couple of tightens so I went to the clamp method and no more leaks from that rear seal. | | | | | Joined: Jan 2002 Posts: 2,843 'Bolter | | 'Bolter Joined: Jan 2002 Posts: 2,843 | I use 2 hose clamps with a short piece of flat aluminum between them to keep that rear collar tight. One clamp on the collar, the other on the shaft. The flat aluminum piece clamped between them keeps the collar from rotating. I believe Phak1 is correct about the cork packing wearing in. My collar continued loosing after a couple of tightens so I went to the clamp method and no more leaks from that rear seal. Me too
Craig My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
| | | | | Joined: Sep 2020 Posts: 3 Moderated | | Moderated Joined: Sep 2020 Posts: 3 | Thanks Jerry, I agree that a bearing or bushing may be worn out to cause vibration and loosening the cap. This problem may have been masked by a worn u joint...not sure 'bout that tho..Time to take it back apart and inspect. Thank you for your reply. Jon | | | | | Joined: Feb 2004 Posts: 29,871 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,871 | OK- - - -we're talking about the knurled gland nut at the end of a torque tube front housing, right? Either do the hose clamp thing, or just use a small drop of blue LocTite on the threads to keep the nut from backing up.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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