No 1st and reverse gears

[Aliman]

Hi I have a Leyland 285 tractor and am unable to select the 1st and reverse gears rail.
2nd & 3rd, 4th & 5th OK. The tractor has been sitting for 3 or so years, and it was ok before that. Any help would be very appreciated. many thanks Aliman.

 

[heaty]

I remember our 1060 doing this from time to time and we used to be able to unlock it by moving the selectors with a long screwdriver through the gearbox oil filler plug next to the gear stick. Same gearbox I think on your pre synchro 285