The Triumph Dolomite Club - Discussion Forum

How do you remove the detent covers on a Sprint 3 rail selector? They look like cup seals. Do you have to destroy and replace to remove?

cleverusername wrote:How do you remove the detent covers on a Sprint 3 rail selector? They look like cup seals. Do you have to destroy and replace to remove?

Do you mean the cover plate where the three selector rods come out of the gearbox top cover

Paul

The reverse rod is stiff. According to the dolomite online manual, the detent mechanism has to removed before disassembling the selector mechanism. The diagram shows what looks like three core plugs and these are in the bottom side of the selector casting. However the manual gives no hint about how to remove these plugs.

Robert 352 from Christchurch has done this very job in order to change the seals. Suggest you PM him.

Geoff

Underneath those small core plugs (3 off) is a spring + a ball bearing. Like Robert I too have stripped my selectors down to renew the selector seal which were "o" rings but I replaced them with oil seals - no more leaks now if you want any pictures let me know as I have detailed pictures of the strip down just never got around to doing a write up about it

Paul

Flyfisherman wrote:Underneath those small core plugs (3 off) is a spring + a ball bearing. Like Robert I too have stripped my selectors down to renew the selector seal which were "o" rings but I replaced them with oil seals - no more leaks now if you want any pictures let me know as I have detailed pictures of the strip down just never got around to doing a write up about it

Paul

Thanks, that would be helpful. We can't work out how to remove the plugs without destroying them. They are also impossible to buy.

I am not familiar with the three rail gearbox. If there are any similarities with the Sprint or Stag box I have a suggestion which may help.

The Sprint/Stag box has three O ring seals behind a plate which cannot be replaced unless the rails are removed. I got three lengths of dowel, same diameter as the rails and used them to push the rails out and hold the detent mechanism in place. No need to remove the detent caps, springs and balls. Replacement is the reverse or so the saying goes. Just a suggestion which might be of some help perhaps?

You can remove the detent covers by drilling a small hole somewhere close to the centre in each of them and then inserting a screw and then pulling them out. Care should be taken in drilling the right hand side one, when viewed from underneath the cover. This cover sits over a hardened steel detent pin which controls the engagement of the reverse gear.

The detent covers can be reused and there is no need to worry about an oil leak from the drilled holes for there is a gasket which surrounds holes in which those covers sit.

The 2.5PI and TR6’s which use the same gearbox have the same cover but those covers were screwed in rather than pressed in as is done on the Sprint box.

There is an excellent article on how to overhaul the gearbox cover on the Buckeye Triumph website which shows the three screws which are used in place of those detent covers. It also gives details on how to dismantle and reassemble to the top cover.

See http://www.buckeyetriumphs.org/technica ... xCover.htm

Ideally you need a 5/16 brake spanner to undo square headed bolts which hold the selector forks on the selector shafts. I have purchased a 4 sided socket for this specific purpose for I have removed and replaced the selector rods a number of times.

Flyfisherman / Paul has done some truly excellent work in locating some much more satisfactory vee seals to replace the “o” rings which leak on the top covers. Someone needs to buy him several beers or something and persuade him to do the write up of what he did and how he did it. Failing that I would do it if my arm was really twisted but the credit must be passed back to Paul.

Robert