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-   -   Clutch not disengaging fast enough?? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/clutch-not-disengaging-fast-enough-852703/)

coldsmoke 07-19-09 06:47 PM

Clutch not disengaging fast enough??
 
I have a 91 FC and I seem to have a problem shifting gears whenver I put in clutch fast then shift. the clutch seems slow to react so the shifter doesnt want to go into the next gear since its not fully disengaged and if i force it even more it grinds. If i wait half a second more it will go in but it has that resistance when I try to change it fast. I did a test from neutral I put in clutch fast and shift to first and I get that resistance of the little bit of clutch. Then I put in clutch and held it for a second then shifted and it was perfectly smooth. I bled the clutch with an asisstant and there seems to be no more air now. I changed the shifter bushings and I changed the gear oil for the transmission. I'm puzzled.

RotaryRocket88 07-19-09 07:51 PM

You can adjust the release point of the clutch w/ the rod on the backside of the pedal. There's a locknut, and a rod that connects to the master cylinder. You can rotate the rod to adjust. Is the release point very close to the floor, or do you have a decent amount of stroke before the clutch engages/releases? Maybe fingers on the pressure plate just aren't being pressed in far enough when you push the pedal down.

clokker 07-19-09 08:07 PM

I'd wonder if this isn't more a synchro issue rather than a "slow" clutch.

coldsmoke 07-19-09 08:13 PM

Having too much freeplay can do that?


The car has only 80,000 miles on it and it has that half a second resistance on every single gear but lessens in higher gears. All when I don't granny shift.

Wouldn't that test with neutral and first confirm its not the synchros? It so feels like its the clutch not fully disengaging fast enough

RotaryRocket88 07-19-09 09:46 PM


Originally Posted by coldsmoke (Post 9368332)
Having too much freeplay can do that?


The car has only 80,000 miles on it and it has that half a second resistance on every single gear but lessens in higher gears. All when I don't granny shift.

Wouldn't that test with neutral and first confirm its not the synchros? It so feels like its the clutch not fully disengaging fast enough

I don't know if it would make it feel "slow", but having the clutch travel out of spec can make shifting grind. Just throwing ideas out there, and it's something that's not too difficult to check.

Worn synchros will grind less if you rev match on downshifts or ease it into gear gently. I guess if you pause for a moment right before a shift it could feel like it goes into gear better, if the RPMs drop towards the level they will be at after the shift.

12AllWays 07-19-09 10:05 PM

Isn't it true that if a pilot bearing is worn or not greased well it will give the same symptoms as a clutch that is not dissengaging all the way?
If so it could also be that...


Originally Posted by coldsmoke (Post 9368332)
Having too much freeplay can do that?


The car has only 80,000 miles on it and it has that half a second resistance on every single gear but lessens in higher gears. All when I don't granny shift.

Wouldn't that test with neutral and first confirm its not the synchros? It so feels like its the clutch not fully disengaging fast enough


stylEmon 07-20-09 01:15 AM

there are some good suggestions mentioned here. i just Went through thid last week so here is my 2 cents. i somehow managed to bust the pivot ball, clutch fork and pilot bearing all together! for real! after we replaced those three items, i would try to put the car in gear and it would roll slightly with the clutch engaged. since i recently replaced all the hydraulics and the fork/bearing/ball, the only thing left was the clutch pedal itself. adjusted that and now she shifts like a dream.
good luck.

coldsmoke 07-21-09 12:09 AM


Originally Posted by 12AllWays (Post 9368536)
Isn't it true that if a pilot bearing is worn or not greased well it will give the same symptoms as a clutch that is not dissengaging all the way?
If so it could also be that...

Anyone else have experience witih this?







I still think it's something in the clutch hydralic system. Could a failing/bad slave cylinder (or even master) cause something like this?

drifter403 07-21-09 01:36 AM

just adjust the clutch... bleed the master clutch cylinder...

stylEmon 07-21-09 09:20 AM


Anyone else have experience witih this?
YES! I posted just above you....

This is true, a busted pivot ball will make the clutch not engage properly.
So can a busted clip on the clutch fork.
And a broken pilot bearing.
And worn out/clogged clutch hydraulics.
The same with the clutch pedal it's self, being out of adjustment.

Check ALL these things out one at a time. Start with the easiest, the pedal. Then try the hydraulics. To get to the pivot ball, bearing and fork, you have to take the tranny out.

coldsmoke 07-21-09 04:28 PM


Originally Posted by stylEmon (Post 9371774)
YES! I posted just above you....

This is true, a busted pivot ball will make the clutch not engage properly.
So can a busted clip on the clutch fork.
And a broken pilot bearing.
And worn out/clogged clutch hydraulics.
The same with the clutch pedal it's self, being out of adjustment.

Check ALL these things out one at a time. Start with the easiest, the pedal. Then try the hydraulics. To get to the pivot ball, bearing and fork, you have to take the tranny out.

Ok so I corrected the freeplay and then went for a test drive. It seemed good but when the car got fully warmed up its the same old thing again. If i try to shift fast I get the resistance and i feel it most from first to second.

I guess the next step would be to replace all the clutch fluid (since it's not clean at all) and bleed it again. and if that doesnt work then replace slave then master cylinder.

stylEmon 07-21-09 04:41 PM

Is the clutch fluid black? If so, the hydraulics need to be rebuilt. The rubber pieces melt away with time.

If it's not black, bleed the slave cylinder.

If that doesn't do the trick, move on to the pilot bearing and fork.

EDIT* Hydraulic Rebuilt kits from MazdaTrix are cheap.

RotaryRocket88 07-21-09 05:36 PM

Rebuilding the hydraulics is sounding like a good idea. A quick test you might want to do is to have someone press the clutch pedal, while you watch the slave cylinder. Have them tell you when the pedal is all the way to the floor, so you can see if the piston extends at the same time, or if it has some sort of delay. It will also be a good chance to observe anything else that might be out of the ordinary.

stylEmon 07-21-09 05:53 PM

Great idea. That's how we got mine working well.

coldsmoke 07-21-09 10:03 PM


Originally Posted by stylEmon (Post 9372799)
Is the clutch fluid black? If so, the hydraulics need to be rebuilt. The rubber pieces melt away with time.

If it's not black, bleed the slave cylinder.

If that doesn't do the trick, move on to the pilot bearing and fork.

EDIT* Hydraulic Rebuilt kits from MazdaTrix are cheap.


Yes the fluid was very black and smelly and I just diluted it when I bled it with fresh stuff, didnt think it mattered. I'll drain it completely then refill and bleed then.


Originally Posted by RotaryRocket88 (Post 9372923)
Rebuilding the hydraulics is sounding like a good idea. A quick test you might want to do is to have someone press the clutch pedal, while you watch the slave cylinder. Have them tell you when the pedal is all the way to the floor, so you can see if the piston extends at the same time, or if it has some sort of delay. It will also be a good chance to observe anything else that might be out of the ordinary.

I'll be sure to do that test after i replace the fluid. Also i'm going to try RP gearmax since I heard nothing but praise and how some people had drastic benefits from it.

And if it still has the problem looks like i'll be rebuilding both cylinders :rolleyes:




Good suggestions guys.

stylEmon 07-21-09 10:29 PM

You should definitely rebuild the master and slave together. Your old ones are shot if the fluid is black and smelly.

If this doesn't completely fix it, you'll be dropping the tranny next.

coldsmoke 07-21-09 10:35 PM


Originally Posted by stylEmon (Post 9373568)
You should definitely rebuild the master and slave together. Your old ones are shot if the fluid is black and smelly.

If this doesn't completely fix it, you'll be dropping the tranny next.


Ah ok, i'll be sure to order those tomorrow. So after I have both of those back in I just pour in the fresh fluid and bleed until no more air?

What about bench bleeding which i've read about?

coldsmoke 10-03-10 02:21 AM

:shooter:

FelixIsGod29X 10-03-10 03:59 PM

pour fluid in and bleed.

spinitsidewayz 10-04-10 10:59 PM

I know it might sound silly, but when was the last time you changed transmission oil? And why did you revive the thread after a year? O_o


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