- My model of MX-5 is: 2007 NC 2.0
- I’m based near: Blackburn
- I’m looking for technical help or recommendations on: Clutch Pedal adjustment
Hi, I can see that very similar posts have been made in the past. I’ve tried to read as much as possible and looked through the workshop manuals. I understand that the MX5 requires quite a lot of pedal travel for the clutch compared to most other cars.
When I got the car, the clutch pedal had to be pressed as far as possible to the floor to engage 1st/reverse and pretty much all the way for other gears. Occasionally it would struggle to go into 1st/reverse. I found out about the pedal and adjusted it and it improved things but it was still almost to the floor.
I adjusted it again, this time as far as it would go so that the threaded bar was still fully through the nut that it locks with. Even after this, the clutch starts to engage when the pedal is only about 1cm up from the bottom. From what I can tell in the manual, it shouldn’t be this low but I can’t adjust it any further without the threaded bar only being partially engaged with the nut which seems unsafe to me.
The clutch hasn’t ever slipped, so I don’t think that it is worn out. The clutch doesn’t improve if I pump the pedal so I don’t think there is air in the system. There is a correct amount of brake fluid in the reservoir. I don’t believe it is getting worse over time.
I’m not great at describing things, so the image shows how D is normally protruding through C (shown in blue) but I have adjusted it so that it is now flush with the back of C (shown in red). I don’t think adjusting it further out would be safe as then fewer threads would be in contact between C and D so is there another reason the pedal has to be pressed so far?
Thanks for your time
I’m not sure if the forum etiquette is to reply to the nearest post to match my issue to ask questions or to make a new thread for it. Some places frown on reviving old threads.
Am I out of luck with this? it can’t be that far to the floor without there being an issue somewhere can it?
Is it possible the slave cylinder isn’t achieving full extension? Is there a reference value you can check the piston length with clutch dully depressed? I think if it doesn’t fully extend then the engagement will be much sooner and possibly drag.
Take it to someone who knows what they’re doing.
Years ago on one of our old Mk2 Jags we could not understand why the slave cylinder was not doing its job with not enough travel available, even after bleeding and no visible leaks, so fitted a new one and the problem went away.
When I took apart the old one much of the internal ‘adjust’ spring had rusted/gummed solid because the clutch fluid had probably never been changed - it was black and syrupy when we bled it .
Now, Mazda Service never bleeds the clutch when the brake fluid is changed every two years, unless you specifically insist on it! The Niseko clutch fluid was black when I bought it “serviced” the day before, and this afternoon so was that from the 25AE, also recently “serviced”.
So now I’ve adjusted it, and bled it, and the clutch is at last nice; no more crunches from the gearbox .
Hi thanks for this. I do have the same issue on my Niseko. I am so desperate that I was planning to replace the entire clutch assembly but here you tell me there may be a cheaper solution!
Are you referring to the slave cylinder? Did you replace it with an OEM one?
May I also ask you which oil you used (and if it’s all right for the shifter turret too)?
It was the old Jag that needed a new slave all those years ago.
Fortunately I’ve not had to replace one on an MX5, modern materials and modern fluids are much better. BUT the fluid requires regular maintenance, because it is hygroscopic and will absorb water vapour from the air. On these MX5s it should be replaced every two years, regardless of mileage.
If the outside of the slave is clean and dry of any fluid, it is not leaking and therefore highly unlikely to be faulty.
Bleed the slave first; this is easy if you are happy crawling around under cars AND have the right kit AND know what you are doing. Otherwise ask a professional.
Being old and creaky now, I normally ask for it to be done at a service when the car is up on a lift, then it’s only a five minute job for the garage while they bleed the brakes.
The clutch master cylinder shares its fluid reservoir with the brakes, and you must use the correct brake fluid (ALWAYS use a new sealed can/bottle of DOT3 or DOT4). Old fluid can compromise braking and clutch operation.
After correctly adjusting the pedal end of the system, its operation was still inadequate and the next service and MOT is not due for months. Therefore I had no choice and I bled the 25AE clutch slave myself. Problem solved.
I suspect the fluid in the slave might have been nine years old because some dealers tend to overlook it when they change the brake fluid.
Shifter turret uses gearbox oil, and yours should not need touching unless the mileage is excessive.
I’d suggest one of 3 issues here.
Slave cylinder, clutch presssure plate or requires bleeding and fluid change.
Put the rod back to where it was and go for. Fluid change, clutch bleed first, this will be the cheapest first option.
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I am quite new with cars (I’ve been tinkering a bit with bikes). While mx5 seem to be easy cars to work on, they are a bit more complex than a bike (with often a single oil reserve for the whole gearbox/engine).
I will go step by step: I will try adjusting the pedal a bit, then bleeding and refilling the oil, then I will consider inspecting and eventually replacing the master and/or slave cylinder(s) and if the issue is still there, clutch bearing
Thank you
