Lotus Elan and Lotus Elan Plus 2 Forums

question concerning the "locating marks" on the synchro hubs.

I cannot for the life of me see any indications of a locating mark.
It is quite possible the gearbox has been apart in the past.
When I replace the snap ring I'll take another long look.


My question is how critical is the locating mark to operation?
Nothing is machined in place once everything is on the mainshaft during manufacturing is it?
Shouldn't all parts be symmetrical and able to be rotated out of "alignment" and still operate correctly?

I struggled to find markings on mine, too. Though I think I finally found some on the drive gear and synch ring, I never could on the other one. I experimented with the rings turning them tooth by tooth and did find some orientations slid quite freely and others with resistance... so I eventually settled on what seemed the smoothest orientation.

Before disassembly it is best practice to mark the position of the inner synchro hub to the mainshaft splines and also the position of the inner synchro hub with the outer sleeve so they can all be reassembled back in their original positions. This is because the mating surfaces all wear as a set with each other. If you forget it's probably no big deal although there will be an increased wear rate of the parts until they have worn in and once again established a "set" with each other - i.e all the micro high points worn down so full surface contact is once again established.

That makes perfect sense. I could not for the life of me understand the relevance of locating marks on a new box.

Next one gets marked on disassembly