gearbox problem coming down from 4th

Sounds like the pawl spring, it's very tempermental and tiny adjustments can make a huge difference. Old Britt's website has a good section on how to adjust.

As John says pawl/spring most likely. I can get a similar issue if I allow my boot to rest on the lever and restrict the action slightly,or stiff crossover ?.

+1 for the spring, make sure it's inthe right way up (dog leg to the bottom) &the pins shouldjust about touch the pawl. The spring ends should be just about parallel (followingthe Mick Hemmings video).

It's always surprises me how critical this spring is (& itjust looks like a bit of old wire coat-hanger) - I always wish for an extra hand when refitting my mk III cover!

As most people have suggested, the main suspect is the pawl spring. The shape and position of this item has to be near perfect or it will cause gear changing problems. It is very easy to put the spring back wrong with the dog-leg at the top. Usually this is due to looking at the open side of the cover in an inverted position.

The other possible cause of duff changes in one direction is a crack in the shoulder of the gearchange return spring. The crack can not generally be seen until the spring is removed from the cover.

The two attached photos show the important chunks.

Attachments
Gearchange%20Spring.jpg
gearchange-return-spring-jpg