Darren Groves Posted September 30, 2018 Report Share Posted September 30, 2018 Are the synchro rings in the 3 Rail/3 Synchro gearbox interchangeable with those in the 3 Rail/4 Synchro gearbox. Link to comment Share on other sites More sharing options...
Pete Lewis Posted September 30, 2018 Report Share Posted September 30, 2018 on the basis 3sync are 148409 and 4 sync are 150326 there are differences in the two baulk rings possibly in cone angles or tooth chamfer angles , dont know the detail , have both somewhere hidden away might have a look tomorrow for some clues Pete 1 Link to comment Share on other sites More sharing options...
Darren Groves Posted September 30, 2018 Author Report Share Posted September 30, 2018 Thanks Pete Out of interest then, why did 148409 supersede 113797, the later is listed for 3rd/4th Hub but NLA. Darren Link to comment Share on other sites More sharing options...
Pete Lewis Posted September 30, 2018 Report Share Posted September 30, 2018 It would be great in triumph drawings were online we coils all see the upgrades, suffix changes and part number revisons Right now of top of my head ....no idea Pete 1 Link to comment Share on other sites More sharing options...
johny Posted October 2, 2018 Report Share Posted October 2, 2018 It is a bit confusing but I believe the earlier 148409 was used in both 3 and 4 sync 3 rail boxes (for example GT6 1 & 2 and Vit 1 & 2). Then the 3 rail box was modified in various ways (presumably all mods at the same time?) and 150328 ring (150326 is a digit out Pete) was used from then on including the single rail units. I think all use just one type of ring or the other and theyre shouldnt be interchangeable although sometimes they do turn up in the wrong places and it would be interesting to know how well those boxes functioned...... Link to comment Share on other sites More sharing options...
68vitesse Posted October 2, 2018 Report Share Posted October 2, 2018 (edited) Always known them as thick rings, early, thin rings 150328, late, same external diameter but early have smaller internal diameter hence the ring is thicker. Regards Paul Edited October 2, 2018 by 68vitesse Changed picture. Link to comment Share on other sites More sharing options...
johny Posted October 2, 2018 Report Share Posted October 2, 2018 Thanks Paul. Yes the later type obviously have more surface area for gripping and synchronising plus theres no way theyre interchangeable! Link to comment Share on other sites More sharing options...
JumpingFrog Posted October 3, 2018 Report Share Posted October 3, 2018 On 30/09/2018 at 18:59, Darren Groves said: Thanks Pete Out of interest then, why did 148409 supersede 113797, the later is listed for 3rd/4th Hub but NLA. Darren Apologies for not actually answering the question, but interested in the differences between 148409 and 113797. I took a few old 3-rail boxes apart last year for the Mongol Rally car and found a difference in the synchro rings in one gearbox. No idea if the gearbox was original to the car (registered early 1967) or even if the rings are original to the gearbox, but everything else was identical to the other boxes. At any rate they weren't doing a lot of synchronising so they were either completely worn out (they look it) or match up to different gears (cone angle?). Canley's list them as interchangeable (at least 113797 says use 148409)... Later type, 148409: From eBay, listing for an 113797, looks to have the narrower channels interrupting the ridges as in my first picture. Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 3, 2018 Report Share Posted October 3, 2018 The channels aid removal of oil so all a upgrade evolution in baulk ring design Pete Link to comment Share on other sites More sharing options...
68vitesse Posted October 3, 2018 Report Share Posted October 3, 2018 So unless I'm confused. 113797 used in three rail three and four syncro box and can be replaced with 148409 150328 used in later three rail four syncro box, fitted to GT6Ill and early Dolomite 1850 and used in all single rail boxes. Regards Paul Link to comment Share on other sites More sharing options...
johny Posted October 5, 2018 Report Share Posted October 5, 2018 Correct Paul, that seems to be the current understanding? Link to comment Share on other sites More sharing options...
Darren Groves Posted October 8, 2018 Author Report Share Posted October 8, 2018 On 03/10/2018 at 21:31, 68vitesse said: So unless I'm confused. 113797 used in three rail three and four syncro box and can be replaced with 148409 150328 used in later three rail four syncro box, fitted to GT6Ill and early Dolomite 1850 and used in all single rail boxes. Regards Paul Sorry, still a bit confused...?..... Does this mean all 4 synchro gearboxes, whether 3 rail or single rail use the later synchro ring 150328 and just the 3 Rail/3 Synchro gearboxes use 113797/148409.....looking at Canleys & Rimmers website, that's what they seem to list. Darren Link to comment Share on other sites More sharing options...
johny Posted October 8, 2018 Report Share Posted October 8, 2018 On 03/10/2018 at 22:31, 68vitesse said: So unless I'm confused. 113797 used in three rail three and four syncro box and can be replaced with 148409 150328 used in later three rail four syncro box, fitted to GT6Ill and early Dolomite 1850 and used in all single rail boxes. Regards Paul Hi Darren, it means what Paul put here although to be entirely correct Spitfires, logically, also used the 150328 in their 3 rail 4 synchro boxes at around the same time as the GT6 III and Dolly 1850 before all models went over to single rails.... Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now