problem with pedal biting point after fitting helix clutch

aaronw

aaronw

Member +
hi,

i fitted my 4puk helix autosport paddle clutch few days ago.

with the clutch flat on the flor it was asif it wasnt even down,would stall,and only change gear when engine is off.

what we did was put a longer bit of rod in the master cylinder to hold the bearing closer to the pressure plate,but i can now drive it but i cant do quick shifts,still knoches in if trieing to do quickly.

needless to say i only had the car on the road for 23 hours like this,but wasnt forced into gear at any point as i dont want to do damage.

a mate told me its a 'common' problem.

the guy at the garage was concerned if we made the rod any longer it would touch the presure plate :-/

any ideas? many thanks and rep will be added.
 
Ted

Ted

Member +
hi mate, you know the master cylinder rod inside the car is adjustable? or did you mean the slave cylinder? obviously you fitted the clutch plate the right way round?

i had a similar problem with a clutch a while back- ended up changing the pressure plate, must have got a dud one.
 
aaronw

aaronw

Member +
the rod inside the master cylinder,yeh it was fully extended. is that what you mean?

clutch plate can only go one way im sure!? as it sits flat against the flywheel,otherwise the pressure plate wouldnt fit tight and flat against the flywheel?

i bought this cluch few months ago,had little use,and the guy wont reply to me,but it was mentioned the pressure plate could be flatter.

thanks for the reply.
 
S

steveep82

Member +
there is an adjuster bolt on the clutch pedal itself, have you extended that? If that doesnt work and its all bled correctly then its a pressure plate issue, ive had it before, and after speaking to dave at tm development, it seems many others have as well, not heard of it being a problem with the helix though. As you say, its pretty impossible to fit the paddle the wrong way around!
 
aaronw

aaronw

Member +
ah ok,the pedal itself. thatll no doubt sort it. i didnt know about that.

thanks ted,pc18 and steve, will need to add rep when im a paid member again,but i wont forget.

much appreciated, Aaron
 
weeJohn

weeJohn

Lifer
It doesnt need its own release bearing in it to work does it??

It sounds like the release bearing is far to far away from the pressure plate and throwing it forward enough to release the puk. When the clutch is out can you push the end of the fork toward the turbo any ammount? If you can you need to take up that slack before it will work. A longer rod is one way to go or you could attach a bit of flat plate about 3mm thick and use it as a new mounting braket for the slave cylinder. You would need to use coutersunk bolts to hold it to the box and drill new holes in it to mount the cylinder to.
 
350ep70gr

350ep70gr

Member +
weeJohn said:
It doesnt need its own release bearing in it to work does it??

It sounds like the release bearing is far to far away from the pressure plate and throwing it forward enough to release the puk. When the clutch is out can you push the end of the fork toward the turbo any ammount? If you can you need to take up that slack before it will work. A longer rod is one way to go or you could attach a bit of flat plate about 3mm thick and use it as a new mounting braket for the slave cylinder. You would need to use coutersunk bolts to hold it to the box and drill new holes in it to mount the cylinder to.
Click to expand...

John the case at least on my situation is a bit different. You know slave cylinder rod can do a travell lets say 3cm with the petal free and petal on the floor.But harder clutch plates require lets say 4cm of travel to engage and disengage fully. So what i say for the rod and what you say about the base of the slave cylinder mod is just a temporary solution cause in the real world you steal 1cm by the longer rod.Means the bearing sees some pressure on the clutch plate all the time.It isnt a force to make the clutch slip tho..but for a daily driver isnt the best. What we need in our situation is a slave cylinder with a longer travel if it is exist any.
My slave cylinder rod was extended for 1.5cm and the clutch was disengaging at about the very bottom of the floor. If i had a carpet in the car..i would have a prob.Now i have a rod extended by 2 cm and clutch is releasing at about 2cm before petal hits the floor. The solution is that you need to find a way to push the fork further down so the 3cm travel of the slave cylinder will be enough to release. I will try to put my slave cylinder under an angle so the rod is touching the fork further down so the 3 cm travel is enough to move the fork and release it safely without to much pressure on the bearing. I have xtreme pressure plate tho..!
My clutch is advertized as a corolla Gts or something and i think that maybe this car has a different step and a different master cylinder...dont know for sure tho..Just a guess..Maybe someone can clear this up by p/n..Ha ha ha!!

The other solution i can think is a modification on the little ball at the middle behind the fork..but you need to remove the gearbox to try this..
Chris
 
HYBRID

HYBRID

Super Moderator <a href="http://www.toyotagtturbo.
when using exedy or helix type peddal clutches, to get the clutch to fully disengage, first you must extend the slave cylinder rod by 3mm, then adjust accordingly from inside the clutch pedal :) its normal procedure on these type of clutches... sometimes on organic clutches as well..

kon
 
finx

finx

Member +
Basically what kon and the others have said about adjusting the pedal/master pin is spot on.
And chris was touching on the issue in brief correctly as well

I have run into a few case's over the years where cars and semi trucks with full custom made clutch kits and off the shelf ones where even with the pedal adjustment at full it wont disengage the clutch properly .

Lengthening the pin is one way of going about it, but be warned if you make it too long you will have constant pressure of the release bearing on the pressure plate which will cause premature ware on the clutch plate.
OR another scenario of an extended slave pin is you can actually over stroke the pressure plate and it will get to a point where it can start to re-engage the clutch making it hard to grab/select gears at higher loads/rpm.

The problem is caused because of the greater pressure exertion needed upon the heavier duty pressure plate to release the clamp on the clutch plate.
Furthermore in some cases the overall thickness of the pressure plate is less than that of factory or in the case of someone running a Toms, or TRD or similar flywheel it will be thinner than that of a factory unit thus bringing the whole clutch assembly closer to the engine and further away from the release bearing/stoke/pivot rendering the stock stroke of the release bearing and fork to fall short of enough to disengage the clutch

There are a few ways of going about correcting these circumstances

In the case of the clutch and flywheel being the same overall thickness as stock, you sometimes just require an adjustment to the clutch pedal / master cylinder pin.
If that isnt enough in the case of a heavier duty pressure plate you require a sleeved slave cylinder. Thus lowering the volume of the slave cylinder in relation to the master and increasing the pressure of the hydrolic system to overcoming the stronger pressure plate without need of lengthening the slave pin.
A slave cylinder with a longer stroke may seem the logical solution but the stroke of the release in this case is less of the issue, its the force required to release the pressure plate.

In the case of a thinner overall thickness in the clutch kit or flywheel or both the best way to overcome this is to put a washer of corresponding thickness under the release fork pivot.
To do this you need to work out the ratio of the forks travel distance from pin side to release bearing side as the pivot is not in the center so you have a certain amount of extra stroke on the release bearing side for every mm on the slave side (cant remember exactly what the figure is for a starlet) and from this calculate the amount of extra stroke you need for the release bearing to fully disengage the pressure plate.
By putting a washer under the pivot as opposed to lengthening the slave pin you dont shorten the distance between the release bearings rest position and the pressure plate any where near as much so the release bearing wont be resting on the pressure plate at its idle/rest position but you still increase the distance at which the release bearing pivots towards the pressure plate giving you the extra stroke required to properly disengage the clutch

most stock pressure plates disengage between 3-5mm of stroke against the plate. VS off the shelf aftermarket or custom made plates with thicker pressure plate fingers and heavier springs which require an average of 7-9mm of stroke to fully disengage


if some of that doesn't make complete sense blame the whiskey


cheers
Ryan
 
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weeJohn

weeJohn

Lifer
Moving the slave cylinder over and lengthening the rod is the same thing, it closes the distance of the release bearing to the pressure plate and the overall travel distance decreses, giving the clutch a chance to disengage. If its done right then you can set it so the release bearing is close to the plate but not hitting it, preventing excess wear.

The clutch master cylinder delivers the same ammount of oil and pressure when the clutch pedal is pushed to the floor each time. Its this ammount of oil that moves the slave cylinder the ammount its designed to move the rod. If more travel is needed from a slave cylinder there is no option but to change the slave unit for another type that travels more for the same ammount of oil being pushed into it. if there is more travel of the rod available after this ammount of oil is pushed into the slave, then there is no way of making it travel any further unless the master cylinder is changed to one which pushes out a larger ammount of oil to the slave cylinder.

Ryan is it possible if a slave cylinder is not able to move a pressure plate with a larger release pressure than stock requires, that the pressure is causing the seals in the master or slave to bypass the oil rather than push it out? I have heard of other rebuild kits but is there any available for the EP clutch cylinders?
 
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G

GP82

Member +
WoW, sounds like this could be a ballache. If you were going to buy an uprated clutch, 4puck or 6 puck, which you can fit and forget about, which clutch (pressure plate + disc) would it be?

What clutches are tried and tested without making all the adjustments. Guess it has to be something similar to the way the stock Toyota clutch operates.

It would maybe a good idea to have input from users of all different clutches and get feedback on how they got on with it?..
 
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