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Has anyone else found this a total pain in the a$$? I replaced the slave cylinder last night as it was leaking from sitting when I had the tranny out for 3 weeks. Well, I got it hooked up fine and all, but when trying to bleed I had some trouble, I don't get the FSM way, mine says top of the master, press clutch 2-3 times, then bleed, and press again, bleed etc, but everytimne you bleed it till the air stops coming out, don't you waste some fluid, so you should have to refill it everytime? right? or am I wrong? Does anybody have any tricks for this? oh, and one time while bleeding, I waited for the air to stop, and it never did, all the fluid just drained first.... that was annoying, but at least it got all that nasty black fluid out :)

By the way, it is a 79 280zx with nissan unit.

Thanks for any help,
ZGimp, Kris

P.S. Maybe I'm just an idiot, if so tell me and I'll start over :)
 

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You have to keep the master as full as possible during the bleeding process. It's easier if you have a helper that's constantly topping off the reservoir. Don't let the level drop too far, or you'll just be pumping air into the system. Get a big bottle of brake fluid and be prepared to waste some. After the bubbles stop, close the bleeder, and your done.
 

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It also helps to get one of those self bleeder kits. Not the mityvac, which sucks the fluid out. This is a tube that goes into a bottle, and once fluid reaches the bottom of the tube, no air can be sucked back in. Mine has a little magnet on it to stick to the frame. All you do is stick the tube on the bleeder valve, crack it open, and then pump away. Easy to keep an eye on the fluid level, and you can see if any air is coming out. Works pretty well.

I hear the Mityvac setup actually sucks too hard on the fluid, and can pull air past the seal in the slave. Also, put some teflon tape around the bleeder valve, as air can seep in when the valve is loosened.
 

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Discussion Starter #4
Thanks

Thanks guys, I'll try putting the teflon tap on, that sounds like a good idea. I may seriously cosidr one of those self blleding kits, as this was a pain even with 2 people! I also got some local advice of having 3 people help... push the slave cyl. in by hand, open the bleeder screw, have one person constanly but slowly pumping the clutch, another topping off the cyl, and me under the car watching till all of the air comes out, I guess I will try all of these, and hopefully it will work, I got close, it is just a little mushy still.

Thanks,
ZGimp
 

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Re: Thanks

i got mity vac and it works good. go to carparts near you get two feet of vac tubing that will fit your valve for bleeding then get a fruit jar put tube in jar and other end on valve and do all prescribed by other z ers. sam
 

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I just had to replace the slave cylinder (in the Napa parking lot, nonetheless) on my '75 Z; it was very simple. I did not bleed it at the master cylinder at all (you didn't remove it, right??), but instead had some poor Napa customer pump and hold the clutch while I bled it at the slave. Of course, keep checking back to the master cylinder and keep it full... bleed until all you get is fluid, no air (you can actually do this from the engine compartment so you don't get a nice brake fluid facial). After a few HUGE bursts of air, it was bled. I now have nice travel on my clutch pedal and shifting is nice and smooth. I was lucky to have changed one on my '77 before I wrecked it, so I knew it was cake.
 

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Discussion Starter #7
Thanks for the reply, I just have onbe question, what do you mean by pump and "hold" the clutch? Hold it on the floor for a moment or??? I think I may try this method first, I have 2 bottles of brake fluid, and only used about a third of the first one after bleeding the thing dry. Though I do feel sory for that poor napa customer who so galantly helped you, or maybe you kidnapped him??? Either way, I feel sory for him :)

Thanks,
ZGimp
 

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This applies to both breaks and clutches.

Press the pedal in question 2 - 3 times and hold your foot on the pedal.

Have the person under the vehicle open the bleed screw and allow the pedal to go all the way to the floor. When it hits bottom tell the person down under to close the bleed screw.

Repeat this process until fresh, clean fluid and no more air comes out of the bleed screw then you are done.

After each third attempt re-fill the master cylinder.

OR

Put Teflon tape on the threads of the bleed screw fitting. Use a hand vacuum pump (mighty vac) on the bleed screw and open the bleed screw 1/8 turn. Increase the vacuum to about 5 inches and let it drop to 0. Repeat until fresh, clean fluid and no more air comes out of the bleed screw then you are done. (do not go higher than 5 inches of vacuum or you will likely induce air back into the system through the bleed screw threads if you did not use enough Teflon tape)

OR

Put Teflon tape on the threads of the bleed screw fitting. Put a piece of tubing on the nipple of the bleed screw, put the other end of the tubing in a suitable receiving container. Open the bleed screw 1/4 to 1/2 turn. Go get your favorite adult beverage. Now, while drinking your beverage, watch the fluid level in the master cylinder and when it gets low add more fluid. Repeat until fresh, clean fluid and no more air comes out of the tubing in the suitable receiving container. This process takes considerably more time than the previous two so ensure that you do not get confused and put your favorite adult beverage in the master cylinder and try to drink the brake fluid.

The principal here is that "Pressure exerted upon a liquid in an enclosed container is equal and non-diminishing in all directions."

Wayne Monteath
Masham, Quebec.
 

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Okay, to do it the "old fashioned" (yet very effective way), you'll need a buddy. First, make sure the reservoir is full (the clutch res is the one under the cute little door on the driver's side). You can leave the cap off, but make sure that NOTHING contaminates the fluid in the res and on the bottom of the cap. Stand on the passenger side with your deep socket and ratchet (can't remember the size now... the one that fits). Loosen the bleeder screw on the slave cylinder, then tighten it WITH YOUR FINGERS. Have your pal pump the clutch pedal, say, oh, 5 times (this is not an exact science, I do it by feel) and then hold it all the way to the floor. While he is holding the pedal to the floor, loosen the bleeder. The first time, you may get nothing. Just do it again. After tightening the screw again, have him pump, then hold the clutch and repeat the whole process. Don't forget to check the res (you don't need to check it when you don't get fluid out). You will know when you start getting air out, as it will make a'lotta noise. You are done when all you get out is fluid and no air. Also, the clutch will "feel good" and you will be able to start it in gear again (yippee!). This is the same exact thing you do to bleed your brakes; start at the farthest bleeder from the fluid source (in these cases, the master cylinder) and move closer until there are no bleeders left. You MAY need to bleed the master after the slave, but I haven't had to on a Z yet. Happy shifting!
 
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