Weird Clutch Problem

[hkz286]

Hello All,

basically I'm having a weird problem with my clutch.

Last year I did a clutch system refresh, this included:

new slave cylinder (Honda)
rebuilding master cylinder (Honda)
new reservoir hose
clutch damper bypass hose (as in straight from the slave to the hard-line)

you can see in detail in this post:
http://www.stanceworks.com/forums/showthread.php?86920-My-old-Honda-NA1-NSX&p=1547244#post1547244

I also replaced the pedal with the type r version and adjusted it as per Kaz instructions.

So all was fine and dandy, worked as expected without any fuss for months before I put it away for winter.

I got the car out from its winter hibernation a month or so ago (goes away in September/October time) and take it for a spin.

Low and behold the clutch starts to slip.

Take it home, have a look and can see a tiny pin hole leak in the clutch line.

Fix that, bleed it up, and take it out again

This time its fine when its cold, the clutch holds no matter what I do. But when its warm, all the play goes out of the clutch and it starts to slip. This goes on until I can get no drive what so ever. I can get gears fine, even when changing faster in high load.

So I have a look online, find that Kaz had posted this:

http://www.nsxprime.com/forum/showthread.php/178420-Clutch-issues-weird-problem?p=1753619&viewfull=1#post1753619

(http://www.nsxprime.com/forum/showthread.php/178420-Clutch-issues-weird-problem?p=1753619&viewfull=1#post1753619)So I have a go at adjusting the pedal again (to Kaz spec) and its better, but still not great. The same symptoms occur (pedal slowly looses its free play until the clutch starts spinning)

So I though maybe it was air still in the system (I have bled it multiple times at this point) so I gravity bled the clutch until I had gone through about half a litre of fluid. There is definitely no air in it.

Adjusted the pedal again to the same spec. Its a lot better, but still, eventually, the free play is lost in the pedal and it starts to slip.

So I'm kind of out of ideas. Unless I'm not adjusting the clutch properly I really don't know what's going on. I'm prepared to except the clutch might be knackered but its seems weird it was fine before winter, then its broke whilst sat still. Also, there is no slip whatsoever when its cold.

I'm also prepared to accept I might have rebuild the master cylinder incorrectly, but again, its weird that it worked perfectly for so long until I got it out this year for spring. There are no leaks or anything untoward visually.

The only thing I can think of is the pin hole leak managed to pull air in the system slowly over winter. Then when I came to drive it, the air caused the pedal adjustment to be out of spec. Then I've been chasing my tail ever since. Like I said, I might have it adjusted incorrectly, but its as per the service manual and kaz video (https://youtu.be/O_e1mc7Rjbc)

Any suggestions would be good.

[m666 edd]

This isn't a proper fix but to gain freeplay adjustment you could remove the round plastic stopper (blue from memory) from the end of the stroke which would give you more adjustment potential to gain freeplay to see it stops the slipping once warmed up. I did this as a rough quick fix (while out on the road) when I had just installed my type R pedal and was just starting a long journey. It stopped the slipping.

[Pride]

How many miles has your clutch done to the best of your knowledge?

[hkz286]

How many miles has your clutch done to the best of your knowledge?

Dunno. The cars has done 70 ish thousand. Like I said it's not impossible that it needs to be changed. But if it does it's the weirdest symptoms of a bad clutch I've ever seen :s

[hkz286]

This isn't a proper fix but to gain freeplay adjustment you could remove the round plastic stopper (blue from memory) from the end of the stroke which would give you more adjustment potential to gain freeplay to see it stops the slipping once warmed up. I did this as a rough quick fix (while out on the road) when I had just installed my type R pedal and was just starting a long journey. It stopped the slipping.

Thanks. That might be a good way to confirm that I just haven't adjusted it properly (or not)

What did you do to finally fix the problem?

[ozon02]

Hi,
I think Pride has given you a good question. I have run 41000 miles and am after the exchange of clutch - I also did not believe. If you change it, it's just OEM.
regards
mario

[NSXGB]

My money is on clutch pedal adjustment, clutch would most likely slip when cold too, not just when warmed up.
Next time when cold, put it in top gear at 30mph & push the accelerator to the floor to check.

[hkz286]

Hi,
I think Pride has given you a good question. I have run 41000 miles and am after the exchange of clutch - I also did not believe. If you change it, it's just OEM.
regards
mario

thanks but I'm not sure I agree the actual clutch is at fault. It's not impossible, but from the behaviour of the car I think it unlikely :)

[hkz286]

My money is on clutch pedal adjustment, clutch would most likely slip when cold too, not just when warmed up.
Next time when cold, put it in top gear at 30mph & push the accelerator to the floor to check.

yeah that's what I keep coming back too. When it's cold, I tried what you suggested, tried hill starts, holding the car on the handbrake and setting off (it just stalled) so I'm fairly sure the clutch isn't at fault :)

[hkz286]

just to update this thread.

A new clutch master cylinder and correct adjustment (after Kaz talked me through it in words of one syllable) have sorted the issue, thanks for the help everyone :)