Clutch hydraulic issues

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gnoplos
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Clutch hydraulic issues

Post by gnoplos » Wed Jun 19, 2019 12:27 pm

Hi everyone, long time fan, first time owner!

I know this probably sounds like I’m beating a dead horse again, but I’ve searched everywhere and couldn’t find the answer it a similar issue to mine (I think).

The problem
When I depress the clutch pedal, there’s absolutely no pressure. The fluid also rises when I press it.

What I’ve tried
1.Bled it (EXTENSIVELY with gravity as well as blocking the clutch pedal while I crack the bleeder. And bench bled the master cylinder)
2. Take the slave cylinder apart. Seems to be working. And I assume if it were going to malfunction, it would either be seized up or it would leak past the seal.
3. Replace the master cylinder with an old one that was in the trunk and it gives the same results.

Things to keep in mind
1.When I purchased the car, the clutch fluid was full so I’m ruling out any major leaks.
2. I still looked for leaks with nothing showing.


Any expertise would be greatly appreciated
1969 1600 jalopy with U20 transplant #24080

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notoptoy
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Re: Clutch hydraulic issues

Post by notoptoy » Wed Jun 19, 2019 10:36 pm

Check the hose, sometimes they get weak and act like a bad water hose with the pressure bulging the hose rather than activating the clutch slave.
Otherwise I would suspect the seals at the master.
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

67.5 SPL311 H20 w/5 speed
65 Impala Convertible
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jrusso07
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Re: Clutch hydraulic issues

Post by jrusso07 » Thu Jun 20, 2019 8:06 am

Agree with the hose "ballooning" under pressure. Do both master cylinders have the fluid rise? That is a sign of a bad master Cylinder.
Joe

1969 SRL311 - Solex
1970 SPL311 - U20 mod
1970 SRL311

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redroadster
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Re: Clutch hydraulic issues

Post by redroadster » Thu Jun 20, 2019 8:41 am

I always ....try to do a bench bleeding with a line and hose recirculating the fluid. 1st
A good helper is worth alot .
a ballooned mc seal can do it too

Mitsubishi makes/made a inline
Clutch 2nd cly( I forget the name they call it) that takes the pressure off holding the clutch on the floor. Eclipse. 3000. Evo, had them. about $100.

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speedbug78
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Re: Clutch hydraulic issues

Post by speedbug78 » Fri Jun 21, 2019 12:07 pm

I had the same problem with mine and it was a bad master cylinder. No fluid leaks, but lots of bleeding produced no pressure at all. Fluid rises when the pedal is pressed. Put on a new master cylinder and problem solved.
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'66 VW Baja
'97 F150
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gnoplos
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Re: Clutch hydraulic issues

Post by gnoplos » Mon Jun 24, 2019 6:15 pm

OP UPDATE:

Alright so I’m starting with replacing the flexible line to the slave (someone replaced it with a metal line), using that metal line to bend back into the master to bench bleed it, and finally bleeding it with a power bleeder.

When I got the braided flexible line, it doesn’t seem right. The fitting at the slave is too short. It also is flat with no type of flare. Is there supposed to be a gasket there or something? Or is my part no good?


EDIT: sorry found what I was looking for. I’ll update when I get the washer
1969 1600 jalopy with U20 transplant #24080

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gnoplos
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Re: Clutch hydraulic issues

Post by gnoplos » Tue Jul 02, 2019 9:40 am

The master cylinder fixed it! It was definitely showing signs of being the issue, I just found it highly unlikely that there were two master cylinders with the same issue.
1969 1600 jalopy with U20 transplant #24080

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speedbug78
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Re: Clutch hydraulic issues

Post by speedbug78 » Tue Jul 02, 2019 2:44 pm

Glad you got it!
Cars:
'69 2000
'66 VW Baja
'97 F150
FED Project
...