Manual Transmission T56 | T5 | MN12 | Clutches | Hydraulics | Shifters

Trying to determine if my master cylinder is bad or if its my slave

Thread Tools
 
Search this Thread
 
Old 05-30-2011, 02:28 AM
  #1  
On The Tree
Thread Starter
iTrader: (1)
 
BigBadVoodoo Daddy's Avatar
 
Join Date: Aug 2009
Location: FRIENDSWOOD TX
Posts: 112
Likes: 0
Received 0 Likes on 0 Posts

Default Trying to determine if my master cylinder is bad or if its my slave

So just like the title says I have already replaced my master cylinder with the auto zone brand and Im still having the same problem. The clutch feels all soft and squishy and doesn't return to the normal at rest position. I bled the hell out of the system when I replaced the master cylinder and the car seemed to work fine for about a week, and now I have the exact same problem all over again. Do you think it could be something wrong with the clutch or what? Very aggravated and ready to get her back on the road. Thanks in advance for the help!
Old 05-30-2011, 11:08 AM
  #2  
TECH Addict
iTrader: (2)
 
Darkman's Avatar
 
Join Date: Apr 2009
Location: Spring, Texas
Posts: 2,167
Likes: 0
Received 5 Likes on 4 Posts
Default

Well it could be the slave, but the fact that worked temporarily points back to air or contaminates in the system. I would bleed it again before throwing parts at it.
Old 05-30-2011, 11:19 AM
  #3  
TECH Fanatic
iTrader: (4)
 
TheBlueKnight's Avatar
 
Join Date: Sep 2008
Location: Nevada
Posts: 1,971
Likes: 0
Received 1 Like on 1 Post

Default

If this was happening to me I'd first check the fluid level in the master resavior. You said it starts to get crappy after about a week? So after it gets crappy check the fluid resavior to make sure you don't have a leak. If it's low I'd look under the car to see if you are dripping fluid from around the bottom of the bell housing (slave leak) or if not that, check under the dash against the firewall where the master bolts up to see if there is fluid leaking (around the firewall or on the carpet could indicate a master leak. Even check under the hood around the master area by the firewall. If it isn't low on fluid I'd go to autozone or whatever parts store you shop at and get a mityvac. You put the tip of the mityvac in the hole on the bottom of the master cylinder resavior and put a vacuum on it (i forget what it is like 12 or something?) While the vacuum is holding I like to pump the clutch pedal a little and wait a couple minutes to see if you start seeing bubbles come up the line. If there are lots of bubble coming up the line you have a leak somewhere and are getting air in your system. If no bubbles, I'd drop the tranny and change out the slave if you just changed the master. I actually had to do this by myself in a parking lot and did it in one day. here is the vid of me doing it. I was a newbie back then and made a couple mistakes but everything went well in the end.

http://www.streetfire.net/video/lear...all_638399.htm
Old 05-30-2011, 07:13 PM
  #4  
On The Tree
Thread Starter
iTrader: (1)
 
BigBadVoodoo Daddy's Avatar
 
Join Date: Aug 2009
Location: FRIENDSWOOD TX
Posts: 112
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by TheBlueKnight
If this was happening to me I'd first check the fluid level in the master resavior. You said it starts to get crappy after about a week? So after it gets crappy check the fluid resavior to make sure you don't have a leak. If it's low I'd look under the car to see if you are dripping fluid from around the bottom of the bell housing (slave leak) or if not that, check under the dash against the firewall where the master bolts up to see if there is fluid leaking (around the firewall or on the carpet could indicate a master leak. Even check under the hood around the master area by the firewall. If it isn't low on fluid I'd go to autozone or whatever parts store you shop at and get a mityvac. You put the tip of the mityvac in the hole on the bottom of the master cylinder resavior and put a vacuum on it (i forget what it is like 12 or something?) While the vacuum is holding I like to pump the clutch pedal a little and wait a couple minutes to see if you start seeing bubbles come up the line. If there are lots of bubble coming up the line you have a leak somewhere and are getting air in your system. If no bubbles, I'd drop the tranny and change out the slave if you just changed the master. I actually had to do this by myself in a parking lot and did it in one day. here is the vid of me doing it. I was a newbie back then and made a couple mistakes but everything went well in the end.

http://www.streetfire.net/video/lear...all_638399.htm

Fluid in the master was crappy but I changed it out and everything was fine for like I said about a week. I also noticed that the fluid level was not dropping in the reservoir nor did I see anything leaking from underneath the car. I bought a mity vac from autozone and I inserted everything into its proper place and saw about 5-7 air bubbles come out at a time after I pumped on the clutch a MILLION times. However after a while the bubbles stopped and that was when I was able to drive the car for about a week. Then after I put the car up for a week I went to drive it again and thats when I noticed I could push the pedal down to start the car but I couldnt use the clutch to put the car in gear and also the pedal felt very soft and squishy. So with all that said you're thinking it might be the slave that needs replacing? Like I said I have bled the hell out of this thing to the point of my left leg feeling like it was about to fall off and then bled it some more and still nothing. Now the car will still start but it wont go into gear at all anymore even after I do bleed the system a MILLION TIMES! Thanks
Old 05-30-2011, 08:45 PM
  #5  
TECH Fanatic
iTrader: (4)
 
TheBlueKnight's Avatar
 
Join Date: Sep 2008
Location: Nevada
Posts: 1,971
Likes: 0
Received 1 Like on 1 Post

Default

Man, I'd change your new master again first just in case you got a bad one. That would be easier than dropping the tranny to get to the slave. If you do do that do the drill mod if you haven't yet, here is my vid on how to do it...

https://ls1tech.com/forums/manual-tr...der-video.html

BTW how are you bleeding your system?
Old 05-30-2011, 09:47 PM
  #6  
On The Tree
Thread Starter
iTrader: (1)
 
BigBadVoodoo Daddy's Avatar
 
Join Date: Aug 2009
Location: FRIENDSWOOD TX
Posts: 112
Likes: 0
Received 0 Likes on 0 Posts

Default

Yup already changed out the master cylinder along with doing the drill mod......Im thinking about trying a new master cylinder, thats not the first time that has been suggested.
Old 06-02-2011, 03:32 AM
  #7  
On The Tree
iTrader: (2)
 
airattack111's Avatar
 
Join Date: Mar 2006
Location: lafayette, louisiana
Posts: 138
Likes: 0
Received 0 Likes on 0 Posts

Default

I have the same problem, clutch is mushy even after thorough bleeding. Been having this problem for 2 years. I managed to bleed it one time to where the clutch worked perfectly, 2 days later it was back to being soft again.

I may try the "jmd" method which lets you "bench bleed" the hydraulics while they are still on the car. I'll let you know how that goes.
Old 06-02-2011, 08:39 AM
  #8  
Staging Lane
 
hixwv's Avatar
 
Join Date: Feb 2011
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default

my clutch has stuck about 1/2 way back out two or three times since i put a new clutch and slave in 2 weeks ago. its broke in now with about 750 miles on it. when she sticks or doesnt come all the way back to me its usually in traffic after ive had to ride it slightly. and also two or three times ive been going from first to second and its like it didnt want to go into gear, it would direct me to 4th lol. all i had to do was slightly move the gearshift back towards first then it would drop right into second. as few times as its done that its not big deal. more worried about the clutch not coming back to me. should i replace the slave? its a daily driver for the summer so is dropping the big buicks for the tick absolutly nessecary? or napa?
Old 06-02-2011, 09:08 AM
  #9  
Staging Lane
 
i'm sofa king's Avatar
 
Join Date: Nov 2004
Location: Bentonville, AR
Posts: 84
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by hixwv
my clutch has stuck about 1/2 way back out two or three times since i put a new clutch and slave in 2 weeks ago. its broke in now with about 750 miles on it. when she sticks or doesnt come all the way back to me its usually in traffic after ive had to ride it slightly.............................
mine does the same if i let it out alittle in traffic. gets worse and worse the more you move up slowly in traffic.

also, my fluid gets nasty after only like 2 days of driving, about 20 miles.

is my master totally shot? the fluid level is never low, and there are no leaks in the garage? think i may just break down and buy a parts store master this weekend.
Old 06-02-2011, 10:04 AM
  #10  
On The Tree
Thread Starter
iTrader: (1)
 
BigBadVoodoo Daddy's Avatar
 
Join Date: Aug 2009
Location: FRIENDSWOOD TX
Posts: 112
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by airattack111
I have the same problem, clutch is mushy even after thorough bleeding. Been having this problem for 2 years. I managed to bleed it one time to where the clutch worked perfectly, 2 days later it was back to being soft again.

I may try the "jmd" method which lets you "bench bleed" the hydraulics while they are still on the car. I'll let you know how that goes.
Think I have decided to just go ahead and replace the slave cylinder as well as the clutch all at the same time since the tranny has to be dropped anyway. Hopefully that fixes my problem!
Old 06-02-2011, 12:09 PM
  #11  
Banned
 
freefallen.1's Avatar
 
Join Date: Jul 2010
Location: Oregon
Posts: 99
Likes: 0
Received 1 Like on 1 Post
Default

You have to watch the AZ parts. I had an order come in on a slave and it did not have the recese on the back for the spacer.Sometimes you just get a bad part. Always best to repace all the hydros at the same time to avoid this.



Quick Reply: Trying to determine if my master cylinder is bad or if its my slave



All times are GMT -5. The time now is 05:59 PM.