Tipidave Posted November 19, 2022 Report Share Posted November 19, 2022 Hi again all, Just to recap…plan is to fit a three rail spitfire box with d type overdrive. I recently tried to purchase a new propshaft (vitesse non overdrive 47”) that stated it was good for herald overdrive conversion but vendor had just sold out. He said that he had a secondhand one available so I Purchased that. It has arrived and measures 48 1/2” with what looks like about max 1 1/4 “ of adjustment in it to shorten. Is it normal to measure from flange to flange? Or some other way. Have I purchased a dud? My understanding is that length needed is 46 1/2”. I am trying to assemble everything I need in advance and now a bit unsure. thanks david Link to comment Share on other sites More sharing options...
johny Posted November 19, 2022 Report Share Posted November 19, 2022 The manual doesnt actually say whether the measurements it gives are between flange faces or u/j centres but presumably its the former as the numbers are fully extended 48.04" and closed 46.79". Then each car is different and your not going to know until everything is in place if youre going to need to move the engine forwards slightly. Remember the movement between engine/gearbox and diff is minimal so as long as theres a little axial float left on the spline (0.5"?) youre good. Talking of the splines how much play is there in the sliding joint? Link to comment Share on other sites More sharing options...
Tipidave Posted November 19, 2022 Author Report Share Posted November 19, 2022 I have test to fiddle with the adjustment and have not inspected the splines. Overall the condition seems better than I was expecting. Link to comment Share on other sites More sharing options...
johny Posted November 19, 2022 Report Share Posted November 19, 2022 Couple of other things, is the sliding joint cap fully screwed on as I think this will change the length of the prop at both fully extended and closed. Also make sure that the u/js are exactly in line at each end because if some one has separated the sliding joint they might not have replaced it in the correct position and this can cause a lot of vibration... Link to comment Share on other sites More sharing options...
johny Posted November 19, 2022 Report Share Posted November 19, 2022 To test spline wear just trying moving the two parts relative to each other (rotational and radial) in all directions and positions.... Link to comment Share on other sites More sharing options...
Tipidave Posted November 19, 2022 Author Report Share Posted November 19, 2022 I will have a fiddle tomorrow 👍thanks for the suggestions Link to comment Share on other sites More sharing options...
Wagger Posted November 19, 2022 Report Share Posted November 19, 2022 My Vitesse propshaft, non overdrive, is 47.625 to 47.75 inches measured flange to flange when fitted. It is mid spline so would be about 48.5in fully extended and 46.875in closed. Needs two people when off to measure it. Stand one end on the floor, hold vertical, use a spirit level to hold the other flange horizontal. Measure extended and compressed. On my car, reversing te engine mounts left to right can move the engine and gearbox about 1/2 inch for and aft. Gearbox mounts to chassis can be slotted or re-drilled. So can the engine mounts. If the engine is moved forward, check bonnet, Carb, steering rack and fan clearances. Try to fit it mid length. Do not fit it fully compressed or fully extended. Looks like yours is the same as the one on my car. Link to comment Share on other sites More sharing options...
Neil Clark Posted November 20, 2022 Report Share Posted November 20, 2022 If you're mobile, a run up the A3 or M3 to Propshaft Services in Feltham (just off the end of the M3 extension towards London) might be worth it. They measure, assess and check the balance for £65. Mine was OK except splines and that the balance was way way out and so they didn't charge for the inspection and instead made a new one for me including UJ's on the the spot for £140.00 plus VAT. Plus free tea and they let me watch the process. Email them in advance. 1 Link to comment Share on other sites More sharing options...
Bfg Posted November 20, 2022 Report Share Posted November 20, 2022 Measurements are taken to the mating-face side of each flange, when they are held square to the tube. This is because different manufacturers may have slightly different yoke sizes, for different ..perhaps uprated, UJ bearings. The shafts telescopic length on a IRS car is to both allow it to be contracted for fitting and then to allow the engine / gearbox and the diff to move on their mounts. Naturally it also accommodates production tolerances ..the distance between gearbox and diff flanges, as well as chassis flex as you fly over hump back bridges.! By coincident, I swapped the driveshaft on my TR4 yesterday, for a new one. < here >. I was pleasantly surprised that it came out of the tunnel without my having to dismantle the exhaust, remove the gearbox cover, or drop the diff, as some TR owners appeared to have needed to do. The shaft should have indexing marks (arrows) by the telescopic spline. The new shaft I bought specified Lithium based grease be used in the spline. As yours is presumably of an unknown age, then I'd undo the knurled cap and pull the spline apart, to clean out the old grease and refill with new. The thin straight shaft next to the spline needs to be smooth so that the grease retaining seal isn't damaged. The mating surfaces of the flanges also need to be clean and free from paint. And even if you use th. same bolts, I'd recommend you to use new nyloc nuts. Neil's suggestion is good, have it checked. And that's good pricing too. Hope that helps, Pete Link to comment Share on other sites More sharing options...
Pete Lewis Posted November 20, 2022 Report Share Posted November 20, 2022 17 hours ago, johny said: how much play is there in the sliding joint? as asked but you dont want any play in the telescope , and for some reason when used on a non live axle they wear terrible when i got my Vit6 the thing was a bag of vibro massages and the splines were completely shot the UJ were fine it was Scrap Pete Link to comment Share on other sites More sharing options...
Tipidave Posted November 20, 2022 Author Report Share Posted November 20, 2022 Thanks for all of the replies. I have thoroughly inspected and measured today and all is well no play at all. No means of adding grease to one of the uj’s so guessing it is a sealed for life bearing. splines all good and no sign of wear or play. accurate measurement is 47” which is correct. However this is the measurement with the slider at shortest length. Still a bit concerned about how to deal with the length if indeed it is 46 1/2 “ that is needed. 1 Link to comment Share on other sites More sharing options...
johny Posted November 20, 2022 Report Share Posted November 20, 2022 Yes the only way to guarantee no problems would be a custom made propshaft but as your mod has been done successfully previously theres a good chance you'll be able to do it one way or another. Let us know for future reference how it works out👍 Link to comment Share on other sites More sharing options...
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