Slipping clutch

[vintagecarman]

I had a Spec stage 2 single disc installed and have driven it over 400 miles. While breaking it in, I drove it very carefully not exceeding 5k rpms . Then out of the blue it started slipping. Could it just need to be adjusted or could the clutch plate burned out?

Any advise?

 

[Larry Bastanza]

You should have end play in the clutch pedal. See page 12-4 in the on line service manual, dimension "B". If there is no play that is why it is slipping.

HTH,
LarryB

 

[hlweyl]

Did they give you specific break-in advice? To me, engine rpm has nothing to do with clutch wear. Once you let the clutch all the way out, it is engaged... period, the clutch is no longer affected by engine rpm until you shift. Clutch wear only occurs when you are releasing the pedal.

Are you sure the clutch is slipping? What symptoms are you getting? It could just be low on fluid which you can check in the clutch master cylinder under the front hood next to the brake fluid reservoir.

Good luck

 

[Larry Bastanza]

You will not get slipping from a hydraulic problem(low fluid, etc), you will get hard shifting. If it is slipping it is a mechanical adjustment or worn out, I doubt the latter after only 400 miles, unless the car has been launched from 4000rpm with EVERY shift.

HTH,
LarryB

 

[vintagecarman]

Symptoms

I was told not to exceed 5k rpms until I had put over 400 miles on the clutch by several people. During the break in period, I attempted to take it over 5K rpms and it did slip. From that point forward I never exceed 5K rpms and babied it.

After a approximately 400 miles It was grabbing perfectly with no slipping then it just went south in a hurry. I checked the clutch fluid reservoir and it is low

 

[hlweyl]

I would check for leaks in the clutch hydraulic system. A few common places are underneath your pedals and if its the slave cylinder you might find some wetness around the tranny area.

 

[vintagecarman]

No Launching!

I had the slave cylinder replaced when I did the clutch. I never launched the car and was continuing to drive it carefully. However, I did drive it the hard before the slippage occurred. The clutch was engaging when the pedal was almost at the very top. Could this problem be as simple as an adjustment?

 

[Larry Bastanza]

Please see above. There NEEDS to be end play. It MAY need this adjustment, let us know what kind of end play you have.

HTH,
LarryB

 

[vintagecarman]

I would have to let the clutch pedal almost all the way out before it would engage. There was very little to no play and the end of the pedal

 

[Larry Bastanza]

See the spec in the service manual and adjust the clutch rod length accordingly. The range is wide 1mm-7mm, I would get it towards the larger play value and see how it goes. It will grab lower on the pedal too.


HTH,
LarryB

 

[vintagecarman]

No Go!

There is no play at the top of the pedal and it’s only slipping when it gets hot. I attempted to adjust the rod length however; there is so much pressure I can’t back of the bolts.

How can I release the pressure to make the adjustment?

 

[Larry Bastanza]

OK, I am sure this is your issue. Certainly makes sense that it slips as it gets hot. These clutchs have very tight tolerances.

I am going to make a suggestion here, but I HAVE NOT DONE THIS, so please think about it and see if it may be possible. Try to lossen up the clutch master cylinder from the front bulkhead, essential backing it off the push rod. Maybe this will give you enough play to adjust it.

Are you saying you cannot loosen the locknut, or you cannot adjsut the rod once the locknut is loose?

HTH,
LarryB

 

[vintagecarman]

I'll give it a try

Correct, I can not get the locknut to move.

I will take your advice and loosen the clutch master cylinder; I can see how that would release the pressure. I am having a hard time understanding why this is happening. I have adjusted it twice before. It was engaging to high and I lowered it down however, I preferred when it grabbed higher and reset it.

Could I of let it out too far? Now when it gets hot the clearance it just that far off to make it slip?

 

[vintagecarman]

Up & running!

Larry,

Thanks for the advice! After loosening the Master cylinder I was able to make the adjustment. I went for a long and hard drive last night and there was no slippage!

 

[Steve]

Larry, what do you do for a living? You are the MAN!!

 

[docjohn]

Its not what he does for a living that matters,it's what he does in his garage for fun that matters to us. He is our local NE guru, who could do this for a living.As it stands now there is'nt enough time in the day to work on all the local cars.

 

[Larry Bastanza]

Well Guys,

Thanks for your kind compliments. For a living I manage a software development division for a large copier company. But...cars are my passion, from building, driving, repairing. Before software I developed hardware, most Motorola 68000 micro design, so as cars started adding ECU's and the like it has gotten really interesting for me.

Many of you in the high tech field know the software/hi-tech business is softening here in the US, with offshore looking very attractive cost wise, even to the US Government .

So you have to have a backup plan, Asimo Motorsport may just be that in the future. It would get real intersting to take the "passion" to the next level. Got to pay off some college tuition for my kids first though.

Vintagecarman - Glad it has all worked out. Spec should be very happy now to know their products will start to be accepted in the NSX community.

Thanks again,
LarryB

 

[vintagecarman]

Prime is right on time

Larry,

Thanks again, your advice was right on and I have had no further problems. As far as Spec being accepted, I like my clutch but feel that there product is an inferior one. I had ordered a stage two dual disc and it failed completely. Although they exchanged it for the single disc, I had to cover the cost of the re-install. While the 1st clutch was in my car I believe it did damage to my third gear. I’m experiencing occasion grinding.

They knew of the problems with the Stage 2 dual disc and still sold it to me. I like the clutch however; I would not recommend Spec!

Your time and help is greatly appreciated!

 

[ffffanman]

Clutch releases near the top with play

I was wondering on my 91 if I can adjust the clutch to engage lower on the pedal. It currently releases near the top which I am not use to? I thought near the top was the norm for this car since I've owned it only for a month!
Thanks so much!
Trev

 

[vintagecarman]

Trev,

Yes! You can adjust where the clutch will engage. I did it when my clutch started to slip Unfortunately, I don’t think I could properly explain how. You should p.m. Larry Bastanza
Undoubtedly he’s the one to tell you how.

 

[Lanjett]

ffffanman- I have a '94, and the clutch does as you describe. There is no slipping but it does not engage until the very top of the motion. The adjustment procedure is described in the service manual, I can photocopy and fax it to you if you would like. Just let me know your fax number. My pedal will also stick at the bottom when depressed after the car has warmed up........ anyone have a remedy for this?

Thanks,

Mickey