Technical Gearbox bits, where do they go 😁

[cinque500]

In a 126 500R box, and I don’t know if this is common to other 500’s, but does the round spring clip go behind or outside the three petals? Also it seems bearly long enough to reach them all? Thanks

 

[bugsymike]

In a 126 500R box, and I don’t know if this is common to other 500’s, but does the round spring clip go behind or outside the three petals? Also it seems bearly long enough to reach them all? Thanks

From memory I would expect the spring to be on the inside, can you see score marks to confirm?

 

[fiat500]

That's part of the synchromesh, and is not common to 500's other than those that have been upgraded.
I remember being in the same position as you, but it's a long time ago. I have a feeling that you fit the spring clip in the groove of the sliding part of the sychro, and push the three fingers down onto the ring as you slide them into the "mating" part.
It sounds like gobbledegook and probably is. So don't force anything.

 

[bugsymike]

That's part of the synchromesh, and is not common to 500's other than those that have been upgraded.
I remember being in the same position as you, but it's a long time ago. I have a feeling that you fit the spring clip in the groove of the sliding part of the sychro, and push the three fingers down onto the ring as you slide them into the "mating" part.
It sounds like gobbledegook and probably is. So don't force anything.

Yes that is what I thought, the inner part of the selector hub sit on the splines of the gear shaft with the three pieces sat in it and the hub slides over the outside of it and a brass synchro cones fits either end, but there should be two of those spring clips one either end on the inside tensioning the three metal pieces or "tabs" as described at the beginning. The brass synchro cones push against the free wheeling gears as clutches to bring the two gears to a matching speed to engage quietly hopefully.

 

[cinque500]

From memory I would expect the spring to be on the inside, can you see score marks to confirm?

I don’t recall there being any wear marks either side but I’ll have a close look tomorrow

 

[cinque500]

That's part of the synchromesh, and is not common to 500's other than those that have been upgraded.
I remember being in the same position as you, but it's a long time ago. I have a feeling that you fit the spring clip in the groove of the sliding part of the sychro, and push the three fingers down onto the ring as you slide them into the "mating" part.
It sounds like gobbledegook and probably is. So don't force anything.

I had the assembly out and in several times and sods law, I fumbled it and those parts sprang out with no obvious way of seeing how it was originally assembled and I can’t find any diagrams. My gut feeling is the spring goes on the inside and pushes the fingers outwards but the spring, be it sitting in or outside, seems barely long enough to act on all three.

 

[cinque500]

Yes that is what I thought, the inner part of the selector hub sit on the splines of the gear shaft with the three pieces sat in it and the hub slides over the outside of it and a brass synchro cones fits either end, but there should be two of those spring clips one either end on the inside tensioning the three metal pieces or "tabs" as described at the beginning. The brass synchro cones push against the free wheeling gears as clutches to bring the two gears to a matching speed to engage quietly hopefully.

From memory there’s another one of these synchromesh assemblies on the other shaft, hope so. If so I’ll take that one apart and have a look, it should reveal all

 

[bugsymike]

From memory there’s another one of these synchromesh assemblies on the other shaft, hope so. If so I’ll take that one apart and have a look, it should reveal all

Or that one will spring apart too.
Does this help explain what I was trying to say?

 

[cinque500]

Or that one will spring apart too.
Does this help explain what I was trying to say?

I never got the chance to spring apart another as there isn’t one. Thanks for the diagram, although it’s different it did inspire me to have another look.
And it’s all good! It’s obvious to me now (it’s an age thing, takes time) that the spring goes inside as the selector fork pushes the dog thing over those three fingers and that’s not possible any other way Thanks for your support bugsymike & pattinatedpeter.