mx5cartalk.com

Have you searched on the big board - if there is an issue, it should be talked about there. There could be something on here too, but I can't remember seeing anything. FWIW (not much ) I haven't heard of a generic issue with NC boxes, certainly not in later cars where you would expect the bugs to have been fixed - the ND gearbox problems spring to mind.

I'd point you at Deckspeed, who built and raced NCs extensively, but I believe Daniel has closed the doors. Targa Racing (Chris Gough) also track NCs, and would be the other source of track-informed advice. Not sure what Mania's experience is with NCs.

Those symptoms remind me of the failure of my NB 5-speed, which started sticking in 3rd, and got steadily worse until it broke. But that was in a hard worked track dríven car, and the problem only manifested itself after a hard workout on track.

Have you bled the air out of the clutch?
My Nissan box wouldn't go into first easily until I bled it.

If the clutch master is leaking, you should be able to see fluid escaping, most likely where the rod goes into the back of the m/c inside the car. I don't know if there is another seal on the rod itself to stop that escaping fluid leaking out - you'd probably smell it too, especially if the heater was in use.

If the slave cylinder is leaking, same same, even a smell of fluid perhaps (if taking a close look). It is usually obvious, because the escaping fluid catches the dirt, but if there is a rubber plug over the end of the slave, it could have a drain to allow the fluid to escape with little to show. See if you can dislodge the rubber plug, and check for moisture inside.

Either way, if there is a leak you should be seeing the reservoir losing fluid - have you had to top it up? If it has been bled, is not losing fluid, has been adjusted, the problem would appear to be on the other side of the slave - up to and including the gearbox. In which case, it might be time for a professional to have a look?

Are you using a bleeder with a non-return valve, or some other way of preventing air entering when you release the pedal between strokes? There's a lot of ways of skinning that cat, but air entering via the bleeder is a sure way of undoing the bleed. And yes, you bleed at the slave.

Try re-bleeding. Cheaper to try than going to dismantle everything.