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Discussion Starter · #1 ·
When my clutch pedal is pushed in, the last inch or so before the floor gets sticky. If it gets to the floor, it sticks momentarily (about one full second) before coming up on its own. Any thoughts where to start looking for the problem? Photos please, if you have any!

Adam
 

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When my clutch pedal is pushed in, the last inch or so before the floor gets sticky. If it gets to the floor, it sticks momentarily (about one full second) before coming up on its own. Any thoughts where to start looking for the problem? Photos please, if you have any!

Adam
I would suspect you have a problem with either the master or slave cylinder, but before jumping to conclusions, have you verified that the clutch pedal is not binding and any return springs are fitted and not stretched and/or broken? If the pedal and springs check out, have you had the hydraulic system for the clutch flushed and filled with correct new fluid? Are you still running the original notoriously prone to failure red plastic hose to the slave cylinder? Lastly have either the master or slave cylinder been serviced recently?
 

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Discussion Starter · #3 ·
I would suspect you have a problem with either the master or slave cylinder, but before jumping to conclusions, have you verified that the clutch pedal is not binding and any return springs are fitted and not stretched and/or broken? If the pedal and springs check out, have you had the hydraulic system for the clutch flushed and filled with correct new fluid? Are you still running the original notoriously prone to failure red plastic hose to the slave cylinder? Lastly have either the master or slave cylinder been serviced recently?
Thanks for the input tesprit. I checked, and I do have a new braided hose replacing the red plastic one. I visually inspected the clutch pedal, and I didn't see any issues with the linkage or springs (not sure how to check for stretching). I also looked in the shop manual, and things appear to be set with in specs. I did notice one think though - the pushrod passes through a gromment in the footwell. When releasing it from the fully depressed position, it tugged at the grommet before coming out. I sprayed a little WD40 on the pushrod, and now the sticking is about 50% improved.

So now, what can you tell me about the grommet or what's behind it? Do you think it's the grommet binding up, or is there something else the pushrod could be sliding against?

Adam
 

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Thanks for the input tesprit. I checked, and I do have a new braided hose replacing the red plastic one. I visually inspected the clutch pedal, and I didn't see any issues with the linkage or springs (not sure how to check for stretching). I also looked in the shop manual, and things appear to be set with in specs. I did notice one think though - the pushrod passes through a gromment in the footwell. When releasing it from the fully depressed position, it tugged at the grommet before coming out. I sprayed a little WD40 on the pushrod, and now the sticking is about 50% improved.

So now, what can you tell me about the grommet or what's behind it? Do you think it's the grommet binding up, or is there something else the pushrod could be sliding against?

Adam
OK, it sounds like you have narrowed down the possibilities to binding of the master cylinder push rod/grommet. The grommet is there to keep dust and dirt from getting into the master cylinder. I don't recall exactly how it looked on my car (I sold mine four years ago), but if it looks like a regular grommet that is pressed into the firewall, try prying it out of the hole so it is just hanging there around the push rod. Try the pedal again and if the pedal doesn't stick any longer you found the culprit in the grommet. Try lubricating the grommet with silicone grease used by plumbers (WD-40 is a solvent that will soften, swell, and eventually ruin the rubber) and reinstall it making sure it is well lubricated and the rod can pass through it easily. If the pedal is still sticking with the grommet pulled out, then I would suspect binding in the master cylinder.

It is most likely that what looks like a grommet is actually the dust boot that is covering the push rod end of the master cylinder. If this is the case, you will need to remove the pin from the push rod clevis at the pedal and unbolt the master cylinder from the firewall. With the master cylinder pulled away from the firewall you can pull the dust boot off the end of the cylinder and slide it up the push rod. You may have to remove the braided line from the master cylinder as well, but if there is enough slack in the line, you can just leave it attached. Be careful throughout this process to not spill any fluid out of the reservoir and if you do, clean it off the paint immediately or it will attack the paint like paint stripper. It may be best to suck as much of the fluid out of the reservoir as possible with a turkey baster before unbolting the master cylinder. With the dust boot pulled, you can see the end of the master cylinder where the push rod contacts the piston and you can check that area for corrosion or leaking fluid. If there is corrosion or leaking you will have to remove the master cylinder for replacement or a rebuild. If you determine that the push rod/piston is sticking in the master cylinder, you definitely have a problem with the master cylinder bore and will have to disassemble the master cylinder to find what has gone wrong. If there is any damage to the cylinder bore or piston, it will have to be sleeved or you will have to replace the master cylinder with a new one.
 

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Discussion Starter · #5 ·
Thanks Dan. I cleaned of all the WD40 and smeared some silicone grease on the grommet and pushrod. Now I'm at about a 60-65% improvement. When I have more time to dig deeper, I will. I just wish I had more working space on this thing...

Thanks again for all your help!

Adam
 
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