• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Puzzled on the clutch

Share this page

M

Midget78

Jedi Trainee
Offline
Hello all. I had rebuilt my slave cylinder and put a hydraulic line on today yet I have a problem. This all started when I went out to my car last week and the master was empty with fluid on the floor. The master didnt show any signs of leaking so I only rebuilt the slave. When I rebuilt the slave I only changed the rubber nose piece. The rubber piston ring I got when I put it on wouldnt allow the piston to work and would just bind in the inside and the spring wouldnt push it back. The old piston ring seemed ok so I put that back on and the piston would then work again. I put the cylinder back on and bled it pretty good to the point when I open the bleeder I get a nice shot of fluid out of it. I got in the car and pushed in the pedal with my foot and it is very limp. For sure it is not good enough to drive and shift properly. I can get it in first but thats it. I dont think there is anything wrong with the clutch as the day I parked it I had no trouble. Im pretty sure my problem is the hydraulic system. The rod from the slave when the cylinder was off I could push in and out easily and was limp. Should that rod be easy to move back and forth by hand with the slave off? Im starting to wonder if my throwout bearing gave out then causing the slave rod to come out and the fluid was able to run through?
Any thoughts on this? Im really concerned with this as I hope its not the clutch.
 
2 thoughts.

1. it's not fully bled

2. there is pitting on the inside of the slave cylinder. I had this on my MC and had to buy a new one. the new kit kept binding - would push in but not slide back out. my guess is that you might need a new slave
 
"The rod from the slave when the cylinder was off I could push in and out easily and was limp. Should that rod be easy to move back and forth by hand with the slave off? "

How far can you push the rod? Short distance or full throw? If short, does it stop firmly, with maybe a click or clunk as when the throw out bearing hits the clutch cover?

If you can push it the full throw, or nearly so, then you may have one or more of the following:

1. Broken throw out bearing. Maybe only one ear broken.

2. Broken throw out bearing fork.

3. Broken fork pivot bolt or mount.

4. Broken clutch release fingers where the throw out bearing rides.

I can't remember, is there an inspection port in the bell housing so you could look in and see? Might have a rubber plug to keep road grime out.

Jim
 
Whatever else may be wrong, you probably don't have the thing completely bled. These puppies are really tough to bleed completely--do a search of the archives an you'll see all kinds of crying and gnashing of teeth over this.

Everyone have their own methods, but I've found that the classical approach to bleeding seems to work best for me--open the bleeder, push the pedal, close the bleeder, let up the pedal. Repeat until no bubbles come out.
 
I just did a clutch rebuild and would have to agree these are a pain to bleed. The way I did it was by using a combination of a one man bleeding kit here:
Automotive Tune-up and Brake Bleeding Kit
and pumping. I fist added a little Teflon tape around the threads of the screw valve so no air would be pulled in from the sides. Then seated it and the backed it out 1 1/2 turns. Connected my speed pump lines which reached all the way to the clutch reservoir, and the over flow catch sat on the battery shelf in between the hand held pump and the slave cylinder which is nice since the line from the slave cylinder to the overflow is clear and I can see bubbles. I then started pumping the vacuum and pulling fluid through the slave. You have to CONTINUOSLY monitor the clutch reservoir, to low and it sucks air and you have to start all over. Once I got fluid up to the bleeder pot I started pumping on the clutch. 4 pumps, fill reservoir, 4 pumps fill reservoir. In the middle of all of this you will need to cap the clear line and empty the bleeder overflow. Reconnect and continue 4 pumps, fill reservoir. Took me about 15 min and it was good to go!

Alternantly you can go replace you nipple valve with a Speed Bleeder That way you dont need the to do anything but pump and fill the reservoir
Dan
 
Hey guys. I double checked the cylinder with the air being possibly still in there. I used John Twist way of doing it from University Motors way and added some reps on top of how many he suggested. When I open the bleeder I get a nice full stream of fluid coming out. Their seems to be no resistance on the cylinder. I cant see the cylinder rod moving with it mounted as there in zero visibility on the 1500 tranny. It took me quite a while just to get it off and back on with the mounting bolts being hidden. My thinking is something is wrong with the clutch. I remember removing the slave and the remaining cylinder rod which is attached inside the clutch to something, I could grab the rod and easily push it in and out at least and inch or so with no trouble. I thought this was supposed to have resistance on it. Im not sure what to do. Maybe buy a new slave cylinder and put it on but if it ends up being something inside the clutch then I will have to pull the motor out to work on it and be wasting more money. When I rebuilt the slave the insde was pretty nice and had very little piting. After the rebuild it worked good by hand. At this point in the game pulling the motor I have never done nor do I want to do. I just put anew header and intake on this thing a while back and dread pulling everything off again with it running so sound. I did some reading in the different Midget manuals I have and I notice on the 1500 things are different then the other models. I may be wrong but I think the throwout bearing in my clutch is stuck or something. The weird thing is when I parked it I had no trouble until the next morning finding the reservoir empty. I wonder is that last time I engaged the clutch something happened inside which is really why the fluid leaked out of the slave. I remember putting it in reverse and driving it out of the garage into the spot in the driveway and shutting it off. Next day it wouldnt work. Im stressed on this one with everything going on right now. This is my only car and I have no cash from being unemployed.
 
I am 99.9% sure your problem is bleeding. The A-series Spridget is difficult to bleed, the 1500 is IMPOSSIBLE to bleed.

The problem is that the hydraulic line runs above the reservoir creating a bubble in the line that is very difficult to dislodge. If you have the translucent style hydraulic line on your car, you will be able to see the bubble moving back and forth as you pump the pedal.

There are several popular ways of dealing with this. I will tell you mine.

I jack up one side of the car to get the master cylinder reservoir as high as possible. I remove the pedal access plate and use a tire iron or BIG screwdriver as a lever against the pedal. This allows me to pump the pedal outside of the car. I place on old diaper under the master cylinder. I loosen the hydraulic pipe fitting, use the crow bar to depress the pedal, and tighten the fitting before releasing the pedal. It take a bit to get the timing just right, but if you have the translucent line, you should be able to check your progress easily.

Also, did you hone the cylinder when you rebuilt your slave? Did you soak the new piston ring in brake fluid before assembly? If you are using the old ring, odds are your slave is just going to leak out again once you have it bled. If you don't have access to a hone, you can cut a small piece of sand paper, wrap it around your pinky and use that as a hone. Another trick is to slit a dowel rod, put a few small pieces of sand paper in the slit in the dowel, then put the dowel into a drill. Poor man's hone.
 
Morris, thanks for the tips. I think Im going to buy a new slave and just start over. I just pray its not the clutch or anything in it that went bad. I spoke with a few local guys and they said that cylinder rod should have some play in it and not to be too worried (yet). I didnt put on the new O-Ring cause when I did it wouldnt fit right. The one side would flare out then bind on the inside of the cylinder. I would push it in then the spring wouldnt be able to push it back out. I'll soak it in brake fluid for a bit. I did use some light grit sand paper and cleaned the inside bore out and it was pretty smooth. I will try getting the master higher then the line and see if that does it. If none of this works then I know something inside the clutch went bad with no warning.
 
If you can take the line off the clutch master and plug it with a bleeder, then push the pedal should be hard and not move, if it does, the main seal in the clutch master is passing fluid. My brake master was going soft because the wall of the bore was pitted, ate the seal and fluid was escaping through it.
I only open the bleeders a tiny bit, 1/4" turn at most, plenty to let fluid through not so much that you let air in the threads and stuff.
Sounds like your master is pooping out to me but I haven't worked on a 1500 since 1988.
 
That is why I use a little telon tape on the threads, so I can go out a full turn and a half and no air gets through the threads, works like a charm.
Dan
 
Hey gang. Before going to rent a bleeder from the auto store I wanted to try and get the master removed and place it higher then the arch in the hose to help push that air down. There is 2 mounting bolts on the master right next to the brake master. The top bolt I can get off but the bottom one I cant get a wrench or socket onto at all. Either the brake fluid canister is in the way or the fender wall is. The only thing I can see doing is unbolting the entire bracket that both masters are mounted to yet I will have to disconnect the brake lines to do all that. It seems like Im creating more work. The auto staore will rent me the bleeder for $50 and then return the cash when I bring it back but money is tight right now.
 
When I rebuilt the slave, I soaked the rubber piston O-Ring in brake fluid over night then put in on. The piston is very snug in the cylinder bore. Im not sure if this is going to be ok. The old one that was leaking allowed the piston to move really easy in the bore but with the new ring I can barely move it. I put it on and will bleed the system next with the thinking the fluid will move it but Im not sure if its going to work like that?
 
Well, I got her working. The pedal is about 90% tight. In the immediate start of the stroke there is a slight bit of slop which I may go back in a few days and see if there is some small air bubles still in there. But Im good to go. Thanks to all who helped on this one. I feel much better it wasnt the clutch.
 
Back
Top