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Clutch Hydraulics Issues

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Old 05-08-2018, 07:52 PM
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Default Clutch Hydraulics Issues

I was wondering if anyone would be able to help diagnose what might be wrong with my clutch setup. The issue I'm running into is not being able to shift into first or reverse sometimes. I notice it more on the first time shifting or after a while of driving around which makes me think it's a fluid issue of some sort. The fluid would get black after no time at all (less than a day). I decided to order the Supermiata clutch overhaul kit and installed it with the MOTUL 600 as I read in a thread of a similar problem, this is a better fluid to use than regular dot4. I readjusted the clutch rod (going into the master) till there was resistance and then back off a hair. Sometimes it will go into first or reverse relatively easy, sometimes it takes a bit of force but goes in. The problem is when no matter how hard i press, foot to the floor it won't engage. I've done everything that FM suggests for adjustment with the stage 2 clutch that I installed. Took out the green pad for the safety switch so I could get more adjustment because with it in, no amount of adjustment would disengage the clutch. I can push the slave cylinder back into it's bore after adjustment. Shifts into every gear fine with the car off. I wrapped the master in gold heat wrap to try and cut down on the heat it is seeing till I can get my heatshield. Is there some trick I'm missing or something to check? The new fluid seems to have a tiny bit of black in it already after only a couple miles of driving (water in the fluid? It boiling and breaking down?).

Last edited by thebigtuna; 05-08-2018 at 08:03 PM.
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Old 05-08-2018, 08:23 PM
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Have you called FM? There was just someone on M.net that had similar symptoms and the clutch was found to be defective.

I had this exact issue on both my Stage 1s as well.
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Old 05-08-2018, 08:32 PM
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No I didn't even think about calling them to be honest, figured I was just being a noob and would get it figured out. I will give them a call tomorrow morning and see what they say! Thanks for the suggestion!
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Old 05-15-2018, 02:13 PM
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Originally Posted by thebigtuna
The fluid would get black after no time at all (less than a day)..
Slightly off topic, how long is it supposed to take for the fluid to go black? I replaced the slave cylinder and bled my system in early April and it is black already.
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Old 05-17-2018, 09:53 AM
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The clutch fluid tends to start getting dark after even a couple weeks.
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Old 05-17-2018, 10:03 AM
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What flywheel are you running ? Fredb
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Old 07-30-2018, 09:28 PM
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Typically black brake or clutch fluid is due to high wear of the rubber seals inside the cylinder. Basically the "black" or "dark" appearance is actually tiny rubber particles wearing off your seals. This high wear can happen if your fluid isn't compatible with the seals, if the seals are just plain old and have been pressurized a million million times, or if you've had a lot of piston side load which wears the seals.

If this really is on a new clutch then the two I would worry most about would be fluid compatibility and maybe a cylinder installed with the rod side loading the piston heavily. I wouldnt jump and blame FM if some sub-supplier of the rubber seals in China went to an even cheaper rubber compound without letting FM know and suddenly it's not really as compatible with your preferred clutch fluid as you need.
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Old 08-01-2018, 08:30 PM
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I had an issue with my throw out bearing years ago that just took a **** and made it difficult to shift at times. I was using a fm stage 2 clutch and it overwhelmed the bearing.
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Old 08-01-2018, 08:54 PM
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If you can push the slave in and it does not automatically spring back than you have bad hydrualics.
Before ripping out the clutch, I'd make sure my hydraulics are up to snuff for the task at hand. Take a borescope or long reach mirror and lights and look to make sure the TOB and Clutch fork retainer are properly fastened and not crooked. Also check for proper clutch slave throw. I ziptied a measuring stick to the slave, and set my phone up to record as I operated the pedal, while adjusting the master push rod travel/play. You should be getting 5/8" throw at the slave.
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Old 03-14-2019, 12:53 PM
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Woah its been a few months since I've been on MT. I moved shortly after this post and the car has been sitting since then. It's almost driving time in the UP so I'm trying to get her roadworthy again.

I re-adjusted the PPF and the shifts got a little better but not totally. I'm also running into a problem shifting at high rpm/load. I'm thinking motor mounts might fix both problems?

If its not motor mounts, which probably need changed anyways, maybe the TB is not enough to handle it? "I had an issue with my throw out bearing years ago that just took a **** and made it difficult to shift at times. I was using a fm stage 2 clutch and it overwhelmed the bearing". Maybe I have the same issue as Eric.

The tranny has no fluid in it at the moment, should I pull it and try and check that everything is torqued down still? If so I might buy a new TB because they are cheap so why not.

I really doubt it is the hydraulics at this point but I won't rule it out. I've changed both master and slave at least twice and replaced the rubber clutch line with a 949. I've bled it more times than I want to count.

Flywheel was whatever came with the stage 2 happy meal fred.

Been using the ford motorcraft fluid in the tranny. Used it since I've bought the car and shifting was always buttery so I know I did something wrong with the clutch change. Just not sure what yet.
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Old 03-14-2019, 01:00 PM
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Don't run Motul in your clutch. You don't need the heat resistance, and Motul is one of the most hygroscopic fluids on the market (it wears out the fastest from water contamination, IIRC, Motul says change it every SIX MONTHS). It's also a DOT 4. I run cheap DOT 4. IIRC, there was an argument that if you use DOT 5 on our clutch system, because it's an open system, it will eventually gather enough water to rust out the slave cylinder's bore, vs just crapping up the fluid like on 3 or 4.

I ran ATE Typ 200 for a while, but got sick of ordering cans of it off of the internet and paying for shipping. I feel like running Motul 600 for over a year (without changing it) was responsible for one of my rear calipers locking up completely internally.
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Old 03-14-2019, 01:06 PM
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Good to know! Thanks for the info, I'll pick up some regular DOT 4. After I do a full flush/bleed, I'll try what Brain stated above to make sure I am getting full travel before pulling my trans. Start with the easiest thing first.
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