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  • CV Joint/Drivetrain woes!!

    I know it's a long post but please try to stick with it!!

    First off I have a 4age 20v conversion with homemade frame running mini suspension components and 8.4" hubs

    Over the last 12 months or so I have had ongoing issues with vibration through the steering column and having changed the bearings and CVs several times, had tracking, alignment and geometry setup many times, replaced the tyres (incase of flat spots) and had rims straightened I am still no further forward!

    Initially the problem started gradually and would only occur at speeds over say 70MPH but now the steering vibrates from 40MPH and also feels to "bounce" when travelling very slow, maybe 10MPH, as if using oval rims!!

    I am now very desperate

    In a final attempt, I have concluded that the only thing left to replace are the hubs themselves. So I have built up some new hubs with brand new bearings, balljoints etc. and was going to refit swap them over at the weekend. However, when I took the old hubs off there were some significant marks on the CV joint shaft and the outer bearing.

    I will now attempt to add pics!


    drivers side on left and passengers side on right





    driver side outer half of bearing



    passenger side outer half of bearing

    other pics available here http://s1256.photobucket.com/albums/ii483/4agecooper/


    My problem is, what is causing the markings and why. The marking on both the CV joint and bearing are not square which makes me think that somehow the bearing is not sitting flat, but virtually the same on both sides??

    When assembling these bearings previously I made certain that the bearing race was seated completely,placed the matching spacer in beyween the well greased bearings and added new CV joints. When assembling the hubs I torqued up using the "special washer" first, removed not and torqued up with split washer. Then went further to split pin hole. I think doing everything I was supposed to, to the T. But alas still the same problem, even immediately after rebuild.

    Is it possible that my hubs are damaged? And by the same amount?

    I can only assume that the bearing are not sitting properly, which is A causing them to bind on the CV shaft and B allowing the bearings to move around in the race. But why?

    Has any body ever seen this before or does anybody know where I could be going wrong?

    Cheers for any help

    DickyWhizz
    Last edited by dickywhizz75; 28-08-2012, 12:15 AM.
    A little bit of Mini goes a long way!

  • #2
    How do you tighten your CV joint/hub nut ? I ask because there is a situation where it is possible to tighten the nut but leaving play in the bearing. The CV joint needs to be pulled completely through the bearing so that it takes up all the slack. There has been much discussion on here about the use of a thick washer to pre-tension the bearing before putting the c-washer in as if the nut is tightened when the CV is not pulled fully through the bearing the c-washer will clamp the shaft of the CV joint stopping it pulling the CV through the bearing. You are thus tightening against the clamping force of the c-washer not the taking up the play in the bearing.

    The procedure is set out in the Haynes manual (in the older one I have it is in the Supplement chapter at the back rather than in the chapters about the hubs/brakes etc).
    Watsons frame in a standard length front, they said it was impossible ...

    Build Thread - standard length round nose B series with Watsons frame, it is possible

    Comment


    • #3
      Yes, have made a large thick washer as per haynes manual and torqued up bearings to 190ish lbft. Then remove nut and place split washer in and torque up nut to 190ish, then tighten further to single split pin hole.

      In order to get enough torque during pretensioning I am putting the wheel back on and dropping it down and using chocks. I guess I am then undoing the nut before I jack it back up, then I swap the thick washer for the split washer, tighten up as much as possible and then put wheel back on, place car down on floor and then torque up for final fit.

      I have done this at least 3 times in the last 12 months but always using the same method.

      Would I create enough movement in the bearings by jacking it up after I have undone the nut a bit???
      A little bit of Mini goes a long way!

      Comment


      • #4
        have u checked to see if your axles are straight. jack the car up and have someone put your car in 1st gear and idle it. if you see the middle of your axle bounce up and down they are not straight and that is the reason for your bouncy ride.
        Tampa, Florida... Wilson Motor Works.. WMW4LIFE

        Comment


        • #5
          Yep, I have checked that the driveshafts are still straight.

          Surely this would only cause a vibration at high speed rather than the bounce up and down at low speed? Wouldn't the CV joint counter any bend in the driveshaft at low speed?

          When on blocks and in 1st gear the wheels do show some wobble when it is rotating even though I cannot get any movement in the hub (when holding at 3 and 9) when it is static!
          A little bit of Mini goes a long way!

          Comment


          • #6
            Are the drive shaft lengths correct? Maybe cv binding slightly if the shafts were too long or short!!! Long shot but might be possible
            C20XE Build Thread Linky, Click Me

            Comment


            • #7
              Good question.
              I was running for quite a while (2 or 3 years) since the conversion before the problem started to rear it's head. don't think it would be the drive shaft length but will check it out when I get them back together. Cheers
              A little bit of Mini goes a long way!

              Comment


              • #8
                I know its a long shot but what wheels have you got fitted? If you have alloys do you have spigot rings fitted to in the centre of the wheel to make sure the wheel sits centrally on the hub? If the wheels are off centre on the hub this would certainly give the impression of an oval wheel.

                Gavin

                Comment


                • #9
                  I have 13x7 split rim superlights fitted. There is no spigot ring they just mount straight onto the studs. I have had the wheels straightened (slight buckle) and they checked for 'roundness' (apparently) and I also had some new tyres fitted to ensure there were no flatspots on the old tyres.

                  I did also borrow someone elses wheels and the problem was the same.
                  A little bit of Mini goes a long way!

                  Comment


                  • #10
                    Really weird, the only other time I have come across anything like this is on some older Landrover’s and you got something like speed wobble (like on a motor bike) and this was caused by the top and bottom swivels been very loose. I don’t know if there should be a certain amount of tension on the mini hub swivels?

                    Gavin

                    Comment


                    • #11
                      mine are bend slightly (verified during dyno while wheels were off) my car also feels as if its going over tiny hills at lower speeds (15-20 mph base speed limit). then it clears up at about 30, then comes back in force at about 75 as a vibration.
                      Tampa, Florida... Wilson Motor Works.. WMW4LIFE

                      Comment


                      • #12
                        Well that sounds pretty much, like mine. In that case I will definately get the driveshafts checked out, how much 'bend' do you have in yours to create this?
                        A little bit of Mini goes a long way!

                        Comment


                        • #13
                          the hub/bairings are simple, if the wheels+tyres are running true it must be bent driveshafts
                          "yuck ,more like a 3 r2"
                          http://www.youtube.com/watch?feature...&v=tb261HwQNDQ
                          SAY WHAT YOU BELEVE,,BELEVE WHAT YOU LIKE,
                          http://www.youtube.com/watch?feature...&v=3JhaTwP7uuk

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                          • #14
                            Have you checked if your shafts have free play when sat on floor as I had a vibration and mine was too tight on suspension movement all cars have it !!!!

                            Comment


                            • #15
                              Hi, Yes the driveshafts do have some free play when it sits on the floor so don't think they are too long.

                              Hubs/bearings - think I'm gonna have to just bite the bullet and get new CVs and Timken bearings then make absolutely sure I do everything to the letter. Again !

                              Wheels /Tyres - I am pretty sure that these are now straight and true.

                              Driveshafts - will get these checked out, how much 'bend' in the driveshafts is it gonna take to give this effect? Would you see it by eye or do you have to measure it? What is acceptable?
                              A little bit of Mini goes a long way!

                              Comment

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