These NEM-pocket Telex couplers are actually a bit too bulky, in my opinion. If there's any play at all in the coupler pocket mounting, then they'll clobber the studs on points.

You need to dismantle the coupler, and try and adjust it so there's no "droop" at all. Otherwise it won't work. I've just had a look at my one of these locos, and the couplers are well fitted and there's no play (and it *just* clears the studs on pointwork).

So my advice is to fiddle about with it and see if you can reduce the play in the coupler mounting.

I think the new Telex design on the current Insider crocodile is to try and solve this problem by making the mechanism smaller. But they're not inter-changeable with the older ones.

Nigel