Gearbox Blocker Bars
Posted: Sat Jan 25, 2014 1:29 pm
Since shortly after installing my Type 9 Quaife HD SC box I have had a reasonable amount of crunching when changing down from 4th to 3rd. My throttle is super stiff and I have always struggled to blip the throttle on downshifts but I don't know that just that is the cause of my issue as I do not have crunching changing any other gear combination.
Looking into the box today to see if the synchro rings have broken or are worn I can see that everything looks to be in as new condition (the best I can see anyway). I did notice that one of the blocker bars was hanging out as shown in the photo...
It is possible to change gears with it like that but I pushed it back in anyway but after a change from 3rd to 4th and back it pops out again. It does hesitate to change into 3rd ont he garage floor but that just be due to the gears not spinning. The input shaft nose was removed at the time allowing the input shaft to move away from the box by 5mm so maybe this is purely due to that.
Questions:
Is what I am seeing normal? This is the only blocker bar in the box that does it which makes me think something is not right. The Haynes manual I have shows there are springs (more like circlips really) holding the blocker bars in but seeing as only one bar is popping out makes me think the springs are as should be. ???
Is it time for a gearbox overhaul (after only 1000km competitive!!!!! gr gr gr) and can it be stripped with minimal tools?
Also, can somebody tell me what the purpose of the blocker bars is??? As best I can see it appears that they help push the other synchro ring out of the syncro unit so that the new gear's syncro can be engaged???
Looking into the box today to see if the synchro rings have broken or are worn I can see that everything looks to be in as new condition (the best I can see anyway). I did notice that one of the blocker bars was hanging out as shown in the photo...
- Blocker Bar.jpg (79.89 KiB) Viewed 11918 times
It is possible to change gears with it like that but I pushed it back in anyway but after a change from 3rd to 4th and back it pops out again. It does hesitate to change into 3rd ont he garage floor but that just be due to the gears not spinning. The input shaft nose was removed at the time allowing the input shaft to move away from the box by 5mm so maybe this is purely due to that.
Questions:
Is what I am seeing normal? This is the only blocker bar in the box that does it which makes me think something is not right. The Haynes manual I have shows there are springs (more like circlips really) holding the blocker bars in but seeing as only one bar is popping out makes me think the springs are as should be. ???
Is it time for a gearbox overhaul (after only 1000km competitive!!!!! gr gr gr) and can it be stripped with minimal tools?
Also, can somebody tell me what the purpose of the blocker bars is??? As best I can see it appears that they help push the other synchro ring out of the syncro unit so that the new gear's syncro can be engaged???