glang Posted September 26, 2022 Share Posted September 26, 2022 Yes tip not too difficult to inspect, layshaft more difficult. If you do start to hear the noise when driving you really want to overhaul the box! Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 26, 2022 Author Share Posted September 26, 2022 On 25/09/2022 at 17:55, Clive said: As to gearbox noise, I suspect front bearing or mainshaft tip bearing. BINGO! - Main shaft tip looks like it has been chewed by an angry beaver... Layshaft seems in surprisingly good condition - the fretting in the 'photos is where the shaft meets the casting of the box; where the rollers run is pleasantly clean. Shame really as the layshaft is £30 and the mainshaft is £200! Additionally - and it comes as no surprise - the drained oil was golden with synchro wear. Lots to mull over this evening... Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 27, 2022 Author Share Posted September 27, 2022 9 hours ago, Wendy Dawes said: Ken said he would do special deal for club members if you mention it Thank you. I’ll give him a ring! 1 Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 10 hours ago, Banksy82 said: BINGO! - Main shaft tip looks like it has been chewed by an angry beaver... Layshaft seems in surprisingly good condition - the fretting in the 'photos is where the shaft meets the casting of the box; where the rollers run is pleasantly clean. Shame really as the layshaft is £30 and the mainshaft is £200! Yes that tips had it. Dont forget to check the rolling surfaces inside both the input gear and laygear as the layshaft looks so good it may have been previously replaced. Fortunately the outer surfaces being a bigger diameter do wear slower than the inner but once the case hardening goes they are even more difficult to repair... Places that refurb boxes usually have a disclaimer that says all main components must be serviceable🙁 1 Quote Link to comment Share on other sites More sharing options...
standardthread Posted September 27, 2022 Share Posted September 27, 2022 Karl, Given what you have found and had to do I would seriously syphon the oil out of your dif and replace it, you could have cooking oil in there. Pity Triumph stopped putting drain plugs in difs. 1 Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 Cor one thing at a time! Luckily the diffs are much less prone to wear than gearboxes👍 Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 27, 2022 Author Share Posted September 27, 2022 On 25/09/2022 at 18:50, Clive said: A friend has fixed his by machining it round and made a bush, including a scroll to wind oil into the bearing. Quite possible to use a torrington needle roller too if machined to an appropriate size. Just been down to my local engineering firm (not engine / gearbox specialists) and they reckon they might be able to sleeve with something... It will probably cost me in the region of £90 and they are not really sure what to sleeve with. Do you have any idea what your friend used as a bush? Additionally does anyone know what the correct dimension for the mating bore in the input shaft should be? Mine measures .7512 (a thou and a bit over the - I assume 3/4 nominal) is this wear or normal running clearance? Thanks all. Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 Whoa careful, this is a well worn (no pun intended) pathway and Im not sure if a reliable solution has ever been found. Heres some things to consider: sufficient oil must be able to get into the tip bearing and a bush will require more than a roller bearing. if the tip is machined down theres a risk it will snap off in use. any type of failure of the new set up risks damaging the gears which effectively will mean another gearbox is required. My workshop manual says the bore should be 0.7505 to 0.7509 so you have a bit of wear although this is difficult to measure accurately. Phosphor bronze is usually the material used for these type of bushes but theres a lot of side load here as, especially when accelerating, the gears on the mainshaft and laygear try to force themselves away from each other and this has to be resisted by the tip bearing. Triumph eventually improved the situation by going to an 18mm tip diameter in the single rail gearboxes used in the last models.... Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 27, 2022 Author Share Posted September 27, 2022 1 hour ago, glang said: Whoa careful, this is a well worn (no pun intended) pathway and Im not sure if a reliable solution has ever been found. Thanks - I'll do some forum digging! Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 One possibility is to reduce the tip to 12mm and fit a hardened steel inner race. These are available in this size and an outside diameter of 15mm so you could then use a 15 x 19mm needle roller bearing. This is very slightly smaller than the input shaft 3/4" bore but should be close enough to do the job.... Quote Link to comment Share on other sites More sharing options...
Clive Posted September 27, 2022 Share Posted September 27, 2022 Pete used brass (I think) He did add a scroll to wind oil in. As to reliability, 125k seems to be good, But as I said he drives it pretty gently. If I were to get this done, I would look at a bearing race to suit. Ideally one that had its own surcae for the rollers to run on. Nick jones has added a drilling at the root of a tooth to pump oil imto th ebearing, I think he has mentioned this was used on later cars. The drilling needed to be done by a machine shop. Details on the sideways forum somewhere. 1 Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 Clive what do you think of using a 19mm OD needle roller bearing to run in the 3/4" bore (assuming its not damaged) of the input shaft? Quote Link to comment Share on other sites More sharing options...
Amy Wade Posted September 27, 2022 Share Posted September 27, 2022 19 minutes ago, glang said: Clive what do you think of using a 19mm OD needle roller bearing to run in the 3/4" bore (assuming its not damaged) of the input shaft? 19mm is 0.05mm (1.9 thou) smaller than 3/4". That gap would be easily taken up with a bearing retainer such as Loctite 638. Make sure the surfaces are completely clean and degreased before assembly. Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 Unfortunately we're talking about the rollers OD being smaller than the bore they have to run on in the input shaft.... Quote Link to comment Share on other sites More sharing options...
Amy Wade Posted September 27, 2022 Share Posted September 27, 2022 Sorry, I made the assumption the 19mm OD was referring to an outer race dimension. I'll just go back to sleep 💤 Quote Link to comment Share on other sites More sharing options...
glang Posted September 27, 2022 Share Posted September 27, 2022 If only Triumph had used bearings with races, they would have lasted a lot longer and been much easier to overhaul😩 Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 27, 2022 Author Share Posted September 27, 2022 2 hours ago, glang said: One possibility is to reduce the tip to 12mm and fit a hardened steel inner race. These are available in this size and an outside diameter of 15mm so you could then use a 15 x 19mm needle roller bearing. This is very slightly smaller than the input shaft 3/4" bore but should be close enough to do the job.... Fabulous! I was looking at inner races all of last night but didn't think to go larger and metric! I have just spent some time looking at these and it looks like the sleeves are available in 12.5mm an 16mm lengths (the 0.5/0.75 cage I have is 15.9mm in length and it can't be held tightly end for end or it wouldn't work. The caged bearings themselves are available in 13mm or 17mm lengths - I would guess that the 17 would be too long so would have to settle for the shorter 13mm All of these things are reasonable priced so I think I will order some in and ponder them on the bench. I can make up a mock shaft tip from mild steel just to check the fit in the input shaft. The next question is my cheap carbide tooling up to turning the shaft tip!! Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 27, 2022 Author Share Posted September 27, 2022 (edited) 39 minutes ago, Amy Wade said: Sorry, I made the assumption the 19mm OD was referring to an outer race dimension. I'll just go back to sleep 💤 There do exist drawn cup needle rollers in 16mm O/D that I suppose could be Loctited into the input shaft but their I/D is 12mm max and the diameter that the shaft would have to be turned to to fit a 12mm inner race on would be (in my mind) too small! On top of that I would be a little worried about alignment! Edited September 27, 2022 by Banksy82 Quote Link to comment Share on other sites More sharing options...
Wendy Dawes Posted September 27, 2022 Share Posted September 27, 2022 16 minutes ago, Banksy82 said: Fabulous! I was looking at inner races all of last night but didn't think to go larger and metric! I have just spent some time looking at these and it looks like the sleeves are available in 12.5mm an 16mm lengths (the 0.5/0.75 cage I have is 15.9mm in length and it can't be held tightly end for end or it wouldn't work. The caged bearings themselves are available in 13mm or 17mm lengths - I would guess that the 17 would be too long so would have to settle for the shorter 13mm All of these things are reasonable priced so I think I will order some in and ponder them on the bench. I can make up a mock shaft tip from mild steel just to check the fit in the input shaft. The next question is my cheap carbide tooling up to turning the shaft tip!! Local engineering company ?? Quote Link to comment Share on other sites More sharing options...
glang Posted September 28, 2022 Share Posted September 28, 2022 8 hours ago, Banksy82 said: There do exist drawn cup needle rollers in 16mm O/D that I suppose could be Loctited into the input shaft but their I/D is 12mm max and the diameter that the shaft would have to be turned to to fit a 12mm inner race on would be (in my mind) too small! On top of that I would be a little worried about alignment! You could always open up the bore in the input shaft (as Triumph did on the single rail boxes) to allow the fitment of a bigger bearing but in this case with its own outer race. However theres a small oil hole in the gear to help lube the bearing which may no longer be correctly positioned once the bore diameter is changed☹️ The sleeve fitted to the tip could be machined to the correct length but it and the bearing used must leave some axial gap between the two shafts to accomodate any thermal movement... Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 28, 2022 Author Share Posted September 28, 2022 10 hours ago, Wendy Dawes said: Local engineering company ?? Definitely the sensible choice! Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 28, 2022 Author Share Posted September 28, 2022 2 hours ago, glang said: You could always open up the bore in the input shaft (as Triumph did on the single rail boxes) to allow the fitment of a bigger bearing but in this case with its own outer race. However theres a small oil hole in the gear to help lube the bearing which may no longer be correctly positioned once the bore diameter is changed☹️ The sleeve fitted to the tip could be machined to the correct length but it and the bearing used must leave some axial gap between the two shafts to accomodate any thermal movement... Canley Classics have the shaft available for about £190 (quality unknown) so more involved machining starts to become less economically viable... Quote Link to comment Share on other sites More sharing options...
PeteStupps Posted September 29, 2022 Share Posted September 29, 2022 On 28/09/2022 at 09:15, Banksy82 said: Canley Classics have the shaft available for about £190 (quality unknown) so more involved machining starts to become less economically viable... Input or main shaft? Have you called Canley and asked? Dave is usually helpful 1 Quote Link to comment Share on other sites More sharing options...
Banksy82 Posted September 29, 2022 Author Share Posted September 29, 2022 45 minutes ago, PeteStupps said: Input or main shaft? Have you called Canley and asked? Dave is usually helpful Good to know, it is the Main shaft for a 3 rail 4 synchro D type OD box I haven't called yet as I hope to fashion a repair and do not want to waste anyone's time unless I am likely to make a purchase. I should probably clarify that I am not suggesting that the quality is poor - I just don't know! Quote Link to comment Share on other sites More sharing options...
glang Posted September 29, 2022 Share Posted September 29, 2022 Bastuck in Germany seem to be the only place sourcing new gearbox components (not input shafts though) so I think anybody offering mainshafts will get them from there. However have heard of one serious quality issue and very poor reponse from the company... Quote Link to comment Share on other sites More sharing options...
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