Technical Gearbox Issue

[Grumpy1301]

Morning.
First time 126 owner, 1983 air cooled 650.
Driving normally, 3rd became ‘crunchy’ then at a set of lights difficult to engage 1st (non synchro i know) but went in with a slight crunch. Set off and tried to change to 2nd but wouldn’t go in, 3rd engaged instead and that worked, wouldn’t go into 4th. Limped to a car park, stopped but wouldn’t disengage from third until I managed to but with a different neutral position than before. Gears don’t engage at all and the stick feels very heavy trying to engage. Towed back home, dropped the transmission fluid, plug covered in metal filings (normal-ish for old cars on the plug I’m led to believe) but oil itself sparkly with metal under light.

Any suggestions on what this might be and what the fix is? If the worst, does anyone have a 5 speed they want rid of? Many thanks.

 

[dirkdeman]

It could be something relatively simple like the gearchange coupling (for instance: https://webshop.fiat500126.com/en/r...hift-linkage-snubber-with-screws-und-bushings). But sparkly oil is never a good sign so it might be wise to drop the gearbox and check the internals...

Also two observations:
* The 126 gearbox is synchronised on all gears except reverse
* There was never a 5-speed gearbox for the 126, although there are aftermarket addons