clutch master cyl

[Synthesis]

hey everybody,
i just installed a new master cyl and a new slave cyl on my car. since i didn't have anybody around to help me bleed the system, i used my brake bleed vacuum kit.

well, let's just say i had a horrible time (first time bleeding). i ran through a couple bottles of brake fluid last night, and the bubbles kept coming. there would be short periods where there were no bubbles at all, but then they'd come back. i thought that maybe my plastic hose was causing some bubbles, so the next time i had no bubbles, i closed the screw.

here is how i did it: opened bleed screw, pumped until fluid was running, then when it started i kept close watch of the reservoir. i would fill, go under the car, pump a few times, close the screw, check/fill reservoir, etc.

when i checked the clutch pedal, it would go down about 2/3 of the way without any resistance, then it would push in, but be slightly springy coming back up: feels like there is air in there still.

I tried bleeding again - same problem. i am thinking that it may be the fittings on the metal hose on the master cyl.... i can't think of any other source of air. i'm going to buy a flare wrench right now to tighten up the fittings a little more (i rounded off the bolts a bit when i was loosening/tightening them with a regular wrench - and even one of those "extreme grip" ones)

what do you guys think?

oh, and just for the record, the master cyl is probably one of the most frustrating things i've ever worked on, but at least i didn't spill any brake fluid

 

[Synthesis]

maybe it has something to do with the pedal adjust?

 

[Larry Bastanza]

Nothing is wrong, it is just not bled.

The best way to do this is go to the autoparts store and for about $8 you can get a "One Man Bleeder" tool. It is a short hose with a one way check valve. You may need to purchase a smaller ID hose, the clutch bleeder is small. If you do fit the check valve to the end so air cannot go BACK into the line. So the little arrow is pointing away from the bleed valve.

Open the beelder valve and just pump the pedal Steady and even. REMEMBER the reservoir will only get you about 5 pumps, it is not like the brakes, you have to keep it full. If it runs dry, start over. 10 sets of 5 should do it, if there is still too much play just continue.

John's way below will do it too. FYI, I have never had to adjust the pedal when replacing the master, over 20 now.

HTH,
LarryB

 

[zahntech]

maybe it has something to do with the pedal adjust?

count the threads on the old one when you remove it and then set up the new one in the same place.

the flair fittings up at the master and the dist block like to leak if they are not tightend well enough.

Also when you are bleeding it as a one man job it's quite simple if you place a container of new fluid under the car and then run a vaccum hose from the loose bleeder down into the brake fluid...then fill the master res and start pumping..run a pint or more thru and you should be good to go.

 

[zahntech]

Dang it!! larry beat me to it agian!!!:biggrin:

 

[Tom239]

I used a Speed Bleeder (size SB8125L), it simplifies the job.

There's a writeup on the clutch fluid bleeding procedure here.

 

[Synthesis]

Nothing is wrong, it is just not bled.

The best way to do this is go to the autoparts store and for about $8 you can get a "One Man Bleeder" tool. It is a short hose with a one way check valve. You may need to purchase a smaller ID hose, the clutch bleeder is small. If you do fit the check valve to the end so air cannot go BACK into the line. So the little arrow is pointing away from the bleed valve.

Open the beelder valve and just pump the pedal Steady and even. REMEMBER the reservoir will only get you about 5 pumps, it is not like the brakes, you have to keep it full. If it runs dry, start over. 10 sets of 5 should do it, if there is still too much play just continue.

John's way below will do it too. FYI, I have never had to adjust the pedal when replacing the master, over 20 now.

HTH,
LarryB

i will have to try that....
but what do you think could've been the problem with the way i was doing it?
maybe i just didn't do it enough - i didn't think it would take 10 reservoirs to get all the air out....

also, the car is back on the ground now.... do i have to jack it back up and take the shift cables off and all?

thanks

 

[NSXclear]

No, you can reach it from the top through the engine bay. No need to jack up the car either.

 

[Larry Bastanza]

but what do you think could've been the problem with the way i was doing it?

By leaving the bleeder open, you are just moving air bubbles back and forth inside the line, not really bleeding it. Remember when you do brakes, you push the pedal down, then CLOSE the valve before raising it.

HTH,
LarryB

 

[Synthesis]

Thanks to everybody that responded. I ended up doing it the traditional way (2ppl), and it bled very quickly (not sure if i got a good deal of it out doing it the wrong way or not, but i know there is no air in there now)