Clutch engagement point low

[Melvin]

So I have a problem that the clutch starts engaging when lifting my foot up half an inch. But that’s not all, sometimes when I accelerate hard on lets say 2nd gear, and then proceed to change into 3rd gear and release the clutch quickly, suddenly the engagement point changes during that shift, and is now half-way up. Then when changing into 4th, the engagement point is down at the very bottom again.

Also, 1st, 2nd and reverse gear are sometimes difficult to select. It’s at its worst when I’m stationary and idling. But when I shut off the engine, suddenly all gears go in like a warm knife through butter. Selecting a gear while clutch is fully depressed changes the engine sound a little, as if the clutch is slipping while in gear and foot still all the way down on the clutch pedal. However, clutch doesn’t slip at all when in gear, and grabs very good.

So far, I have replaced the slave cylinder, but that didn’t help much.

Could all these issues be linked to the same faulty part? Any suggestions are highly appreciated. The car is a diesel Kia Ceed -2010 with 136k miles on it.

Topic

[college man]

Since the slave is new The master would be next in line. Check that all air is bled
and the fluid is new.

https://www.ericthecarguy.com/faq/solving-transmission-problems

[Melvin]

Is there a way to rule out a faulty transmission/clutch, before putting money on a new master cylinder? Without taking the whole transmission apart?

[Rick Cropper]

It’s highly unlikely you are dealing with a clutch or transmission issue. It is probably one of there things:

1 Air in the system (most likely)

2 Bad master or slave or hose

3 Broken, cracked, bent, etc clutch fork.

I would bleed the system. With clutch hydraulics you have to go very slow. Do a two man bleed but don’t pump it. Just slowly up and down while operating the bleeder. Watch for the level in the master to drop on the up stroke and wait for it to stop dropping before proceeding. If it doesn’t drop pump the pedal with the bleeder closed and watch again. The masters have tiny passages and don’t refill quickly. Patience is key. Also helps to put some kind of clamp on the slave holding it compressed while bleeding.

Also given your initial symptoms of the engagement point changing look for a missing return spring somewhere on the fork. The spring will help push the fluid back into the master and prevent the fork from bouncing. We see that on Subaru turbo pull clutches from time to time. Missing the $6 spring will cause random low engagement.

Rick

[Melvin]

[quote=”GeneralDisorder” post=178781]It’s highly unlikely you are dealing with a clutch or transmission issue. It is probably one of there things:

1 Air in the system (most likely)

2 Bad master or slave or hose

3 Broken, cracked, bent, etc clutch fork.

I would bleed the system. With clutch hydraulics you have to go very slow. Do a two man bleed but don’t pump it. Just slowly up and down while operating the bleeder. Watch for the level in the master to drop on the up stroke and wait for it to stop dropping before proceeding. If it doesn’t drop pump the pedal with the bleeder closed and watch again. The masters have tiny passages and don’t refill quickly. Patience is key. Also helps to put some kind of clamp on the slave holding it compressed while bleeding.

Also given your initial symptoms of the engagement point changing look for a missing return spring somewhere on the fork. The spring will help push the fluid back into the master and prevent the fork from bouncing. We see that on Subaru turbo pull clutches from time to time. Missing the $6 spring will cause random low engagement.

Rick[/quote]

Hey, sorry for the slow reply.

I’ve recently had my friend’s dad, that’s a mechanic, examine my car, and he told me he saw nothing wrong with the hydraulic system. As I said, the slave cylinder is already replaced. He saw no external leaks at the master cylinder. He told me the slave cylinder rod extends about 0.78″ or 2 cm as the clutch pedal is depressed, and he told me that is plenty to disengage the clutch, which also means the master cylinder is doing its job correctly.

He made some adjustment on the clutch pedal itself, and since then, changing gears was very smooth again, but the low engagement point was still the same. He also told me that, if in the near future, the symptoms of having difficulty selecting gears would come back again, after the pedal adjustment that he did, it means it’s time for a new clutch.

Which is exactly what has happened now, a couple weeks after he made the pedal adjustment. I’m now back to having a very difficult time selecting gears, I have to force them in. Reverse and 3rd gear always grinds when selected. To put it in reverse, I now have to shut the car off and start the car with reverse selected. He told me it’s most likely a cracked clutch plate, which would cause the weird engagement points and gear selection difficulty.

Is it safe to assume the clutch needs replacing, or should I not rule out the master cylinder just yet?

He also bled the system for any air. He pumped fluid backwards, starting from the slave cylinder, and let the air escape from the reservoir instead, but that made no difference.

[Rick Cropper]

You should not have to adjust the pedal rod to achieve proper disengagement.

If the clutch is dragging then one of three things is occurring – either the hydraulic system is not pushing the fork far enough, the fork is flexing and about to fail (seen this quite a few times) – they fracture due to wear at the pivot ball and the ball will blow through the pivot or the fracture will cause one of the legs to break away and the fork to twist sideways, or the disc can start coming apart and bits of the spring pack can jam between the flywheel and pressure plate causing dragging – usually this occurs with “spring” packs that are made using elastomer (rubber) springs.

Adjusting the rod will cause the hydraulics to push the fork farther but since the hydraulics are self adjusting they will return to their previous happy adjustment place and the dragging will return. Make sure the slave rod is in contact with the fork AND the piston inside the slave cylinder bore BEFORE you put any pressure on the pedal. If it’s not then the system has to take up all that slack before it moves the fork.

Usually on Subaru’s this is a bad slave cylinder or a fork that’s going out. The elastomer thing I have not seen happen on a Subaru. Last one was a 2006? Scion Tc.

Pumping fluid into the slave is not an effective way to bleed these systems. You MUST remove the slave from it’s mounting and clamp the slave fully compressed with a C clamp, etc. Otherwise air will be trapped above the level of the bleeder. But even if it’s bled correctly, if the slave is bad then it will go back to dragging again in short order.

Rick

[Melvin]

[quote=”GeneralDisorder” post=180637]You should not have to adjust the pedal rod to achieve proper disengagement.

If the clutch is dragging then one of three things is occurring – either the hydraulic system is not pushing the fork far enough, the fork is flexing and about to fail (seen this quite a few times) – they fracture due to wear at the pivot ball and the ball will blow through the pivot or the fracture will cause one of the legs to break away and the fork to twist sideways, or the disc can start coming apart and bits of the spring pack can jam between the flywheel and pressure plate causing dragging – usually this occurs with “spring” packs that are made using elastomer (rubber) springs.

Adjusting the rod will cause the hydraulics to push the fork farther but since the hydraulics are self adjusting they will return to their previous happy adjustment place and the dragging will return. Make sure the slave rod is in contact with the fork AND the piston inside the slave cylinder bore BEFORE you put any pressure on the pedal. If it’s not then the system has to take up all that slack before it moves the fork.

Usually on Subaru’s this is a bad slave cylinder or a fork that’s going out. The elastomer thing I have not seen happen on a Subaru. Last one was a 2006? Scion Tc.

Pumping fluid into the slave is not an effective way to bleed these systems. You MUST remove the slave from it’s mounting and clamp the slave fully compressed with a C clamp, etc. Otherwise air will be trapped above the level of the bleeder. But even if it’s bled correctly, if the slave is bad then it will go back to dragging again in short order.

Rick[/quote]

Slave cylinder is brand new. But it made no difference to the old original one, so I assume the slave cylinder was never the problem.

Depressing the clutch extends the slave rod a consistent 0.78″, which should mean that the hydraulics are working correctly. I have no idea how much the slave cylinder rod is supposed to extend, but i’m guessing that is sufficient to fully disengage the clutch. I have bled the system in every way possible, and every time it’s been done, it’s only fluid coming out right away.

So what I can understand out of this, is that it’s either the clutch fork, or something else inside the transmission. Both that would require a transmission removal?

Many thanks for taking your time to help me out, it’s much appreciated.

[Rick Cropper]

I just remembered something – if the hose from the master to the slave is wet or damp looking it needs to be replaced. We replace a LOT of them from that era.

0.78″ seems much too little. I am still convinced you have a hydraulic issue. This crops up often right after the clutch is replaced. Dragging is the fork not being pushed far enough. To confirm, use a prybar to actuate the fork. If you can now shift without dragging and the fork isn’t twisting, or creaking, etc then the clutch and fork are not the problem.

Rick

[Melvin]

[quote=”GeneralDisorder” post=180717]I just remembered something – if the hose from the master to the slave is wet or damp looking it needs to be replaced. We replace a LOT of them from that era.

0.78″ seems much too little. I am still convinced you have a hydraulic issue. This crops up often right after the clutch is replaced. Dragging is the fork not being pushed far enough. To confirm, use a prybar to actuate the fork. If you can now shift without dragging and the fork isn’t twisting, or creaking, etc then the clutch and fork are not the problem.

Rick[/quote]

The hose was dry and looked okay. It’s steel tubing from the master and then halfway it converts to rubber and continues to the slave.

That was a very good advice to manually actuate the fork. Never really thought of that, i’ll try that out asap.

Also btw, back when i was replacing the slave cylinder, i noticed a thin layer of oil under the transmission housing. But nothing at all was dripping. Someone told me that is normal due to the heat that it works with, and the evaporative propierties of oil. Does that sound right?
.

[Rick Cropper]

Are you saying there was oil under the slave cylinder on top of the transmission bell-housing?

Or are you saying there was oil on the bottom of the transmission under the car?

External oil leakage is never “normal”. Though one could argue it’s so common for the head gaskets on that model to seep oil that it’s fairly unusual to see one that’s dry.

Rick

[Melvin]

[quote=”GeneralDisorder” post=180763]Are you saying there was oil under the slave cylinder on top of the transmission bell-housing?

Or are you saying there was oil on the bottom of the transmission under the car?

External oil leakage is never “normal”. Though one could argue it’s so common for the head gaskets on that model to seep oil that it’s fairly unusual to see one that’s dry.

Rick[/quote]

There was a thin layer of oil under the transmission itself, not from the slave cylinder.

I haven’t seen that many different transmissions from below, so i was just wondering if that is somewhat normal after you’ve been driving the car.

[Rick Cropper]

If it’s not forming drips and you don’t smell it burning off the exhaust pipes then don’t worry about it. Check your fluids regularly and be aware that these models ALWAYS leak oil from the head gaskets so be prepared for that eventuality.

Rick

[Melvin]

[quote=”GeneralDisorder” post=180979]If it’s not forming drips and you don’t smell it burning off the exhaust pipes then don’t worry about it. Check your fluids regularly and be aware that these models ALWAYS leak oil from the head gaskets so be prepared for that eventuality.

Rick[/quote]

Quick update: I had a new clutch plate, pressure plate and throwout bearing replaced. It turned out to be the original pressure plate being worn out, and not in a good shape at all. The engagement point is now a good 2 inches off the floor, where i would consider it very normal. Gear selection is smooth again.

I do still believe however, that i will be needing to replace the master cylinder soon, so I might as well do that. Dumb question now though, but i’ve gotten mixed answers on this one. Do i need to bleed the brakes also after a master cylinder replacement?

[Author]

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