xebec Posted August 3, 2018 Report Share Posted August 3, 2018 Hello, I have a problem with a very stiff/notchy gear change on my GT6 3 Rail overdrive box. I have removed the top cover to see if I could figure out what the problem is but I am not sure what the problem might be therefore hopefully somebody can advise. Please see: https://www.youtube.com/watch?v=MpNz4qfo8nw Sorry that it is very amateurish and not very good quality but hopefully it gives an indication of the problem. Thanks very much, Regards, Ken Link to comment Share on other sites More sharing options...
Nick Jones Posted August 3, 2018 Report Share Posted August 3, 2018 Ken, Posted recently with a similar problem on our mk iv Spitfire. On ours it mostly affects the 3/4 gate though. not sure how to link to that thread via iPad but it's (mistakenly) in the drivetrain and rear axle section. Nick Link to comment Share on other sites More sharing options...
xebec Posted August 3, 2018 Author Report Share Posted August 3, 2018 Okay Nick, Thanks very much. I will have a look at that. Cheers...Ken Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 3, 2018 Report Share Posted August 3, 2018 first thought for 3rd/4th is the pivot bolt on the bottom of the stick is wrong way round this makes it foul the remote casting and gives the gate a sort of ]--) curved selection in 3 .4 many of the spehical balls are soft and tend to jam up make sure its well greased repair kits had a cup washer with a razor edge which minces the top plastic cup , between the 3 rails are balls and short rods to interlock against getting two gears at once , if something in the top cover has gone astray these can baulk the movement the end shaft runs in two 0 rings fitted inside the tower , broken can cause problems , you have to remove the square dowel bolt to remove this shaft not recomended, they can break off , and fitting new 0 rings get chopped refitting the shaft if theres no leaks from the shaft holes leave this alone . let us know how you find things pete Link to comment Share on other sites More sharing options...
xebec Posted August 4, 2018 Author Report Share Posted August 4, 2018 Hi Pete, I have checked the pivot bolt and it appears in the correct position (see photo's). I had a problem with the bush kit (chewed up plastic cup washer) caused by the steel cup washer having a sharp edge. Replacing this (better cup washers acquired) and using plenty of lube on the whole of the kit contents only had a minimum effect on easing the gear selection problem. I have made sure the breather holes are free and these are functioning fine. I am considering whether it is a good idea to move forward on this by removing the plugs at the end of the shafts including the bolts (very tight) and removing the shafts with a view to replacing the balls and plungers, springs etc. Would you consider this to be a worthwhile option as I cannot see any other reason why the gear selection is so notchy and stiff? Appreciate your help and advice. Regards, Ken Link to comment Share on other sites More sharing options...
Nick Jones Posted August 4, 2018 Report Share Posted August 4, 2018 Does it feel stiff and notchy in both 1/2 and 2/4 gates? Is it the same with the remote and box top off the gearbox body? Thanks for the pics clearly showing the air release holes btw, I had been wondering what Pete was on about in our thread -now very clear! Nick Link to comment Share on other sites More sharing options...
xebec Posted August 4, 2018 Author Report Share Posted August 4, 2018 Hi Nick, Going into 1st is reasonably light with a solid click. 1st to 2nd is also reasonable. 1st to 3rd is stiffer although it goes in but with more of a clunk. 2nd to 3rd has the same effect. 3rd to 4th produces more stiffness with a heavy clunk. 2nd to 4th produces the same effect. The major problem I believe is the 3rd and 4th shift which generates more stiffness and more effort to pull it into the gate. I removed the remote and top off the gearbox to see whether it felt the same and it appears that is the case. I cannot detect any difference whether it is on or off which leads me to believe that the problem is in the box top with the selectors. I hope this all makes sense, glad the pics helped... Ken Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 4, 2018 Report Share Posted August 4, 2018 the dowel bolts are a pig and are gorilla tight, best to use a square drive extention back to front to make good contact or the square will round off and then you have the doo doo's mess to sort out its begining to look like some thing is binding the 3/4 shaft so yes strip it down , in bag so you catch the balls which will escape into the grass or under a bench never to be seen again. the welch plugs will pop out easy with a thin drift down the breather holes , there will be a short rod in the 1/2 shaft to prod the interlocking balls , dont loose it Pete Link to comment Share on other sites More sharing options...
Nick Jones Posted August 4, 2018 Report Share Posted August 4, 2018 Sounds quite similar to ours Ken, except ours is ok when cold but stiffens up when hot. Will be very curious to know what you find. I've never taken the selectors apart before, partly because I never had a problem with one before and partly because I prefer the single rail where possible. Controversial I know...... Nick Link to comment Share on other sites More sharing options...
xebec Posted August 4, 2018 Author Report Share Posted August 4, 2018 Thanks for your inputs. I will get to this hopefully soon as it is Bl***y Hot here at the moment 35C+ and is set to remain so for a few days. Phew.... 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