2nd gear syncro is assembled wrongly, just had the same thing on a mk1 cooper,

the gearstick feels like its hitting a rubber block..

If there is a rod change transmission on there, it could be a roll pin interference issue in the coupler at the trans+shifter linkage connection.

You would expect a 67 S to have a 333 three synchro remote with Cooper style remote bolting up from bottom. Is the unit back in the car or are you bench shifting it? Any chance you have installed quick shift kit? Steve (CTR)

And is it a remote shifter? or magic wand or rod type?

Details as to what  exactly happens (or doesn't happen) might be revealing, i.e does the shifter move but 2nd doesn't engage etc. 

Have you talked to whoever rebuilt your transmission?

Just had my 1967 Cooper S transmission rebuilt and I can't engage 2nd gear.  Other gears seem to work ok.  Has any one had this problem?

Bruce

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