[Fot] Triumph 4 speed O/D's and Layshaft bearing failures.

[fubog1]

 Jack the late laygears use a pressed-in "shell" bearing.They can be fitted to the early circlip gears and aren't an issue but the pressed-only have a tendency to walk out and lathe (used as a verb) into the thrust washer so it can't be removed, so nor can the gear.
The wear issue is exacerbated by all of the metal crumbs generated above the area by 1st/reverse gear graunching.
Glen
 
 
-----Original Message-----
From: Jack Wheeler via Fot <fot at autox.team.net>
To: Glenn Franco <brakey6666 at gmail.com>
Cc: Triumph 'Friends of Triumph <fot at autox.team.net>
Sent: Sun, Aug 11, 2019 8:47 am
Subject: Re: [Fot] Triumph 4 speed O/D's and Layshaft bearing failures.

 I have rebuilt many TR-3B through TR-6 gear boxes, both with and without overdrive.  The failure mode you mention is common, where the lay gear grinds into the rear thrust washer, and sometimes into the housing.  However, I have never had trouble removing the lay gear.  Once I remove the thrust washer, the lay gear lifts right out.  Am I missing something?  Are you working on a Spitfire or GT-6 gearbox?
Once again, I pull the rear thrust washer out, generally with the transmission oriented with the bell housing down.  Then, with the gearbox oriented in the upright position, I lift up the end of the lay gear where I have just removed the thrust washer.  Once it clears the boss at the rear of the housing, the lay gear comes right out.
Not sure this is any help, but that's my experience.
Jack Wheeler

    On Saturday, August 10, 2019, 3:52:18 PM EDT, Glenn Franco via Fot <fot at autox.team.net> wrote:  
 
 Just finished another A Type Overdrive rebuild this afternoon. Next one I do I'm going to insist that the owner bring a spare 4 speed for parts or maybe 2.I very rarely find an overdrive transmission that the layshaft bearing next to 1st that hasn't walked and tried to escape the case through the thrust bearing. I have tried in vane to remove the laygear with one that ground its way into the thrust bearing and sometimes the case. I sometimes get the laygear out but in most cases the trans case with the laygear is sent to scrap.Does anyone have a solution, trick, special tool, to ease the laygear out. The normal way is to remove the small thust bearing with a magnet so you can tilt the laygear enough to get it out. I have even once resorted to a " Slugger Slide Hammer" and chain wrapped around the laygear to get it out. Didn't end well however.I did read somewhere that someone is using a tapered roller bearing on that end which would make more sense than the original design.Please adviseThanks in advanceGlennTR6, TR250, Miata, 47 MG TC For Sale, 73 BMW E10 2002 being restored_______________________________________________
fot at autox.team.net

http://www.fot-racing.com

Donate: http://www.team.net/donate.html
Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot
Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/jwheeler1947@yahoo.com


  _______________________________________________
fot at autox.team.net

http://www.fot-racing.com

Donate: http://www.team.net/donate.html
Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot
Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/fubog1@aol.com


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/fot/attachments/20190811/edd3403d/attachment-0001.htm>