Clutch Pedal Drops to Floor
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Clutch Pedal Drops to Floor
Hi, this is my first post so please excuse me if I make any mistakes! My clutch pedal would intermittently drop to the floor, but with a few pumps it would build up pressure. Today, however, I heard/felt a "pop" (at the pedal) and then it dropped to the floor (never to come back). Is this the master cylinder or slave cylinder (or other)? Thanks!
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Re: Clutch Pedal Drops to Floor
Either or probably!
No, seriously, it is a very simple hydraulic system and it sounds like you have lost all fluid due to breakdown.
Have a good look for a fluid leak under the car, check the flexible hydraulic hose and check the state of the slave cylinder for obvious leaks.
My advice is to change BOTH the master and the slave for replacement units with a new hose.
Once one component goes the others may not handle the new pressure.
No, seriously, it is a very simple hydraulic system and it sounds like you have lost all fluid due to breakdown.
Have a good look for a fluid leak under the car, check the flexible hydraulic hose and check the state of the slave cylinder for obvious leaks.
My advice is to change BOTH the master and the slave for replacement units with a new hose.
Once one component goes the others may not handle the new pressure.
Nissanman, just trying to help.
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On the road again!
- spyder
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Re: Clutch Pedal Drops to Floor
There is a spring under the dash which should return the clutch pedal back to its resting point. If you have to pump because the hydraulics are malfunctioning, and the spring broke, I could see the scenario you describe.Sammy66 wrote: ↑Tue Nov 13, 2018 9:20 pm Hi, this is my first post so please excuse me if I make any mistakes! My clutch pedal would intermittently drop to the floor, but with a few pumps it would build up pressure. Today, however, I heard/felt a "pop" (at the pedal) and then it dropped to the floor (never to come back). Is this the master cylinder or slave cylinder (or other)? Thanks!
- redroadster
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Re: Clutch Pedal Drops to Floor
Master cly seal wrinkle ,fluid breaks down the rubber over time
When the wrinkle straightens out it holds the fluid when it dont look out , same on brakes cly
Its why a brake job on a 2.5 3 ton truck includes new master cly every time it needs pads
When the wrinkle straightens out it holds the fluid when it dont look out , same on brakes cly
Its why a brake job on a 2.5 3 ton truck includes new master cly every time it needs pads
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Mitsubishi tech 9 yrs
Volvo, Kia, Toyota too
6 month - Rolls Royce
ASE MASTER TECH 96. - 11
70 SPL 86 Z31 T , Sportster
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Re: Clutch Pedal Drops to Floor
Thanks everyone for your great input!
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Re: Clutch Pedal Drops to Floor
Suggest you get stainless hose, and you might as well replace all the brake lines (3) as well.
Peter Harrison
1970 1600 (Stroker) - TOAD SAN (Eliza)
1970 1600 (Stock) - As Yet Unnamed
Lake Balboa (SFV) , California
1970 1600 (Stroker) - TOAD SAN (Eliza)
1970 1600 (Stock) - As Yet Unnamed
Lake Balboa (SFV) , California
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Re: Clutch Pedal Drops to Floor
Also check the archives about the clutch pedal pin and hole which can get enlarged and ovaled, affecting the clutch arm travel, thus affecting clutch performance. Might as well check all parts of the system, "while you are there".
Linda
Linda
Sadly-Linda has passed away 2022. She was the 311's den mother and drove the first Rare-Parts ball joint project. RIP.
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Re: Clutch Pedal Drops to Floor
You were 100% correct, thanks so much for the input! Do you know where the clutch pedal return spring can be purchased? I do not see it on any of the datsun parts online stores?spyder wrote: ↑Wed Nov 14, 2018 1:59 amThere is a spring under the dash which should return the clutch pedal back to its resting point. If you have to pump because the hydraulics are malfunctioning, and the spring broke, I could see the scenario you describe.Sammy66 wrote: ↑Tue Nov 13, 2018 9:20 pm Hi, this is my first post so please excuse me if I make any mistakes! My clutch pedal would intermittently drop to the floor, but with a few pumps it would build up pressure. Today, however, I heard/felt a "pop" (at the pedal) and then it dropped to the floor (never to come back). Is this the master cylinder or slave cylinder (or other)? Thanks!
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Re: Clutch Pedal Drops to Floor
You were 100% correct, thanks so much for the input! Do you know where the clutch pedal return spring can be purchased? I do not see it on any of the datsun parts online stores?
- fj20spl311
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Re: Clutch Pedal Drops to Floor
First,
You should not be able to "pump" a Clutch Master. I you can, you are likely to bend the clutch fork, pop the piston out of the slave cylinder or Both.
The brake master has a residual valve the allows you to pump the brakes, the clutch should not have this valve.
The clutch system is very simple.
Check the fluid in the master.
Check the spring under the dash and under the car.
Check for leaks under the dash at the firewall and under the car at the slave cylinder.
You should not be able to "pump" a Clutch Master. I you can, you are likely to bend the clutch fork, pop the piston out of the slave cylinder or Both.
The brake master has a residual valve the allows you to pump the brakes, the clutch should not have this valve.
The clutch system is very simple.
Check the fluid in the master.
Check the spring under the dash and under the car.
Check for leaks under the dash at the firewall and under the car at the slave cylinder.
Phil
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67.5 SRL311-00148 Blue (FJ cruiser VOODOO Blue)
67.5 SPL311 FJ20E teal SDS EFI
69 SRL311 SOLD
19 Raptor SCAB