Miata Clutch Job

This is our regular client's Miata. He wanted to replace the clutch, because it was making noise from pilot bearing, and also since it has 212,000 km on odometer.

We installed a new clutch kit made by NKK (Nippon Clutch Co. Ltd.). We have used this company's clutch numerous times, and we've never had any trouble.

Our technician performed the work, but it was hard to get into 1^st and reverse gears - all other gears were OK when the car is running. After he road tested, and put up on hoist, asked me for my opinion. I got into the car and experienced a problem. He had a problem when installing the pilot bearing, so I asked him to remove transmission once again.

We examined in detail the installation of clutch components and/or any possible installation error but none was found. The pilot bearing he installed was still OK, but I replaced it again anyway. At this time the technician noticed that the slave cylinder has a small leak inside its protective boot. So we replaced this at same time. Then we re-installed all the components.

We then took it on a road test, and still had the same problem. It is slightly better this time, but still, it was difficult to shift in gears from a dead stop. When the engine is running and you try to push shifter lever into its 1^st gear position, the shifter lever does not move. As soon as the we turn off the engine shifter lever moves in easily. This tells us that clutch does not disengage fully.

We arrived to the conclusion, it must be the new NKK clutch part. We ordered a Daikin-made clutch (Mazda use Daikin-made clutches) from another supplier.

Voilà, that was it. I have been working on cars for over 45 years, but this is my first experience with the new clutch that does not disengage.

I thought this might be an interesting topic to those whom are involved in the automotive service industry.