classic motorcycle forum

Basically 1947 B32, on the move it selects 1st 2nd and 3rd ok, when changing to 4th it won't go in, and the gear lever has no downward movement whatsoever, solid, but when i try to change from 3rd to 4th without the clutch it slots right in, going back down the box 4th to 3rd goes in fine but the same problem arises when trying to go from 3rd to second and in the same way if i change without the clutch is goes right in sweet as you like.
This also is the same without the engine running, no clutch and it snicks through the gears fine hold the clutch in and the above problems occurs, in this situation with a cable tie around the clutch lever i get it to 3rd and put pressure on the gear lever, no movement but with pressure maintained, with my other hand i back off the pushrod adjuster as soon as pressure is released from the push rod it engages 4th right away with minimal force. I have taken the outer cover off and all of the gubbins is moving freely and correctly adjusted, the mainshaft (where the pushrod goes through) has some endfloat, i removed the inner cover and found that a washer was missing that sits between the nut on the end of the mainshaft and the inner case, i fitted a washer of 1.5mm and put it back together, no endfloat, but my problem is the same but this time without the clutch connected as i was turning the selector with the outer cover off, so i reduced the washer size to 1.00mm this gave me some end float but i am back where i started, perhaps i don't have enough endfloat tge service sheet states 2thou which i have but it seems the less endfloat i have the wiorse the problem becomes, the inside of the box is prestine, any ideas???...........