I need some help! Clutch hydralics questions
#46
Nordschleife Master
Either that way or Sean R's method of pumping the slave 20 or 30 times are great ways to reverse bleed. Also, I would also check for fractures in the hard line that runs from the clutch master to the slave. Just this weekend we experienced this on a a 79 car from repeated clutch cover/slave removal. Genikz also had this issue and each of us only realized this after hours of attempted bleeding.
#47
Rennlist Member
Thread Starter
[QUOTE=MJ928;9945207]Either that way or Sean R's method of pumping the slave 20 or 30 times are great ways to reverse bleed. Also, I would also check for fractures in the hard line that runs from the clutch master to the slave. Just this weekend we experienced this on a a 79 car from repeated clutch cover/slave removal. Genikz also had this issue and each of us only realized this after hours of attempted bleeding.[/QUOTE
wouldnt you see some fluid around ?? I dont think the hard line is a problem, but i wouldnt rule out anything yet. the pressure bleeder seem to get the fluid out and seem to a decent job . I'm thinking the slave is the issue, in thinking though the problem.
wouldnt you see some fluid around ?? I dont think the hard line is a problem, but i wouldnt rule out anything yet. the pressure bleeder seem to get the fluid out and seem to a decent job . I'm thinking the slave is the issue, in thinking though the problem.
#48
Rennlist Member
Thread Starter
Greg,
again, all the H adusters are just as i left them 3 years ago. locked in position. alll dowels accounted for. all gaps still the 1mm i left them at. agian, the ONLY issue the H adjusters will ever have being locked in position, willl be if the discs whear more than .5mm......... that aint going to happen, due to fact that after near 10 years, i can still see the writing on the discs themselves with the part number ink showing.
so, your FUD is a little off and unwarrented. dont use your position here to advice irrisponsibly. your concern is unjustified and incorrect, clearly. You are an amazingly smart guy, so dont guess when you dont know the answer to a problem
also, back to the wear patterns of the destroyed discs shown. the pressure plate and rear disc will always fail first, especially if you are a clutch dragger. the pressure plate starts the force and its progressive from that point moving toward the INT and then the flywheel.
anyway, just bought at new Slave cylinder. should have it by tomorrow. I found a new master, that was in my racer part bag i take to the track. what is the part numbrer that is correct for it?? are their differences from a new S4 to a 84 US??? or are all the masters the same?
thanks
Mk
again, all the H adusters are just as i left them 3 years ago. locked in position. alll dowels accounted for. all gaps still the 1mm i left them at. agian, the ONLY issue the H adjusters will ever have being locked in position, willl be if the discs whear more than .5mm......... that aint going to happen, due to fact that after near 10 years, i can still see the writing on the discs themselves with the part number ink showing.
so, your FUD is a little off and unwarrented. dont use your position here to advice irrisponsibly. your concern is unjustified and incorrect, clearly. You are an amazingly smart guy, so dont guess when you dont know the answer to a problem
also, back to the wear patterns of the destroyed discs shown. the pressure plate and rear disc will always fail first, especially if you are a clutch dragger. the pressure plate starts the force and its progressive from that point moving toward the INT and then the flywheel.
anyway, just bought at new Slave cylinder. should have it by tomorrow. I found a new master, that was in my racer part bag i take to the track. what is the part numbrer that is correct for it?? are their differences from a new S4 to a 84 US??? or are all the masters the same?
thanks
Mk
#49
Racer
With #2 I indeed meant what Micheal's picture is showing. As the clutch and brake fluid comes from the same reservoir, when you depress the brake pedal, the fluid is pushed into the slave and UPWARDS to the reservoir. Advantages: no power bleeder needed, and, more impotantly, air in a fluid naturally flows up. Air bubbles are just pushed through the system to the reservoir where they escape.
With #3 I meant that I loosened the locknut on the spring adjuster on the clutch pedal. There is a thread somewhere that lists the parameters for the set up. Cant find that thread right now, but iirc the measurements were different for different model years. A proper set up pushes the pedal back just beyond the tipping point, while at the same time not having to use too much force to depress.
I was amazed how accurate the set up needs to be for a proper feel in the pedal. Anything off by a couple millimeter or more was definately noticeable or would result in the pedal staying down all too easily...
Hated to work upside down in the footwell though, but worth the effort.
Good luck and I hope to read a positive result soon!
Leo 1984 S2 euro 5 spd
With #3 I meant that I loosened the locknut on the spring adjuster on the clutch pedal. There is a thread somewhere that lists the parameters for the set up. Cant find that thread right now, but iirc the measurements were different for different model years. A proper set up pushes the pedal back just beyond the tipping point, while at the same time not having to use too much force to depress.
I was amazed how accurate the set up needs to be for a proper feel in the pedal. Anything off by a couple millimeter or more was definately noticeable or would result in the pedal staying down all too easily...
Hated to work upside down in the footwell though, but worth the effort.
Good luck and I hope to read a positive result soon!
Leo 1984 S2 euro 5 spd
#50
Racer
https://rennlist.com/forums/928-foru...e-fixed-2.html
Here it is: see picture in the thread, 43mm for the pedal helper spring adjustment. And preload the clutch pedal to the rod that pushes in.
Leo
Here it is: see picture in the thread, 43mm for the pedal helper spring adjustment. And preload the clutch pedal to the rod that pushes in.
Leo
#51
Rennlist Member
Thread Starter
https://rennlist.com/forums/928-foru...e-fixed-2.html
Here it is: see picture in the thread, 43mm for the pedal helper spring adjustment. And preload the clutch pedal to the rod that pushes in.
Leo
Here it is: see picture in the thread, 43mm for the pedal helper spring adjustment. And preload the clutch pedal to the rod that pushes in.
Leo
With #2 I indeed meant what Micheal's picture is showing. As the clutch and brake fluid comes from the same reservoir, when you depress the brake pedal, the fluid is pushed into the slave and UPWARDS to the reservoir. Advantages: no power bleeder needed, and, more impotantly, air in a fluid naturally flows up. Air bubbles are just pushed through the system to the reservoir where they escape.
With #3 I meant that I loosened the locknut on the spring adjuster on the clutch pedal. There is a thread somewhere that lists the parameters for the set up. Cant find that thread right now, but iirc the measurements were different for different model years. A proper set up pushes the pedal back just beyond the tipping point, while at the same time not having to use too much force to depress.
I was amazed how accurate the set up needs to be for a proper feel in the pedal. Anything off by a couple millimeter or more was definately noticeable or would result in the pedal staying down all too easily...
Hated to work upside down in the footwell though, but worth the effort.
Good luck and I hope to read a positive result soon!
Leo 1984 S2 euro 5 spd
With #3 I meant that I loosened the locknut on the spring adjuster on the clutch pedal. There is a thread somewhere that lists the parameters for the set up. Cant find that thread right now, but iirc the measurements were different for different model years. A proper set up pushes the pedal back just beyond the tipping point, while at the same time not having to use too much force to depress.
I was amazed how accurate the set up needs to be for a proper feel in the pedal. Anything off by a couple millimeter or more was definately noticeable or would result in the pedal staying down all too easily...
Hated to work upside down in the footwell though, but worth the effort.
Good luck and I hope to read a positive result soon!
Leo 1984 S2 euro 5 spd
this i think is the problem. certainly not due to the H adjusters locked in to perfect position.
ill have the new slave on after it arrives tomorrow. and we will see.
thanks for all the input
#53
Rennlist Member
Thread Starter
OK, Just got back from a comprehensive test. partially depressed in neutral, the clutch pedal doesnt go down, proving the check valve in the master is working, and that its something induced by the clutch pack and T/O bearing , fork assembly to the actuator rod. only happens when the vibration allows for the slave rod to be pushed back in slightly due to vibration. since we know the rod doesnt fully extend, it needs viagra or to be replaced with a younger slave.
tomorrow will be the determimnation, but i am willing to bet that the slave is the problem based on the symptoms.
tomorrow will be the determimnation, but i am willing to bet that the slave is the problem based on the symptoms.
#54
Rennlist Member
Thread Starter
haven't looked at this thread as I thought it would be all over long ago.......once the new parts are at last installed either use the brake pedal method or reverse bleed by pumping the slave many times (+20)........using the pwr bleeder doesnt get all the air out.....btdt not so long ago
did you try power bleeder and some hand held pedal cycles too? that seemed to work. anyway, i dont have the extra brake line, so ill do it the old fashon way and see what i get. is there a way to prime the slave? put fluid in it so the bleed is a little less time consuming? I was thinking about putting the end in a pool of brake fluid , with the shaft all the way in and let the springs draw fluid into the assembly. that way when you go to bleed it, you are half way there to start.
#56
Rennlist Member
#57
Rennlist Member
Thread Starter
You could power bleed then do the reverse bleed.......that way you'll get most of the system full of fluid before bleeding out the last of the air.
An importnant note is that the clutch pedal must be in the fully released position so the master piston doesn't obstruct the reverse fluid flow to the brake fluid reservoir.
use a good Dot 4 fluid.........good luck
An importnant note is that the clutch pedal must be in the fully released position so the master piston doesn't obstruct the reverse fluid flow to the brake fluid reservoir.
use a good Dot 4 fluid.........good luck
good idea on the pressure bleed and reverse bleed. Ill see if i can rig up something.
#58
Racer
You can even do a road side bleed. Or track pits bleed.
Did you get the slave installed?
Leo.
#59
Rennlist Member
Thread Starter
All you need is a plastic or some rubber hose long enough to route from brake caliper nipple to slave nipple. Local hardware store or autoparts store. I used an old rubber fuel hose.
You can even do a road side bleed. Or track pits bleed.
Did you get the slave installed?
Leo.
You can even do a road side bleed. Or track pits bleed.
Did you get the slave installed?
Leo.
then, im going to drive it up to sears point (Sonoma Raceway) and hang out with a team owner that needs an instructor this weekend. maybe by luck, i can swindle a license and get out there a race or do a time trial , so bringing my stuff just in case! worst case, the race car is the BEST for long trips. still one of the best road cars ever, even in race form!!!
#60
Rennlist Member
Thread Starter
UGGGGGGGG 4 hours later, stilll no clutch !! i cant bleed the darn thing. all the stuff i use is breaking around me.. the bleeder broke, tried to repair it, but it leaks at the seal still at the reservior. (mcgivered it)
but no pedal!!! ahhhhhhhh! and i got the wrong one. (S4 and 84 version) i need the '80 version because i have the old style lower bell housing, so i had to bend the lines very carefully to adapt . took about an hour to mount it up. the two types are 90 degrees out of mechanical angle Now, its all mounted, and i hope there is no difference between the pushrods or the slave. dont think there is , but you never know. anywayy, i cant get it to bleed.
i guess i might have to rig up the reverse bleed. why is this so hard!!!!!
hate this kind of stuff!
help!!! what about the two man technique. press down, close valve, repeat, etc.???????
i got to go to sears in the morning! ahhhhhhh!
but no pedal!!! ahhhhhhhh! and i got the wrong one. (S4 and 84 version) i need the '80 version because i have the old style lower bell housing, so i had to bend the lines very carefully to adapt . took about an hour to mount it up. the two types are 90 degrees out of mechanical angle Now, its all mounted, and i hope there is no difference between the pushrods or the slave. dont think there is , but you never know. anywayy, i cant get it to bleed.
i guess i might have to rig up the reverse bleed. why is this so hard!!!!!
hate this kind of stuff!
help!!! what about the two man technique. press down, close valve, repeat, etc.???????
i got to go to sears in the morning! ahhhhhhh!
Last edited by mark kibort; 10-26-2012 at 11:55 PM.