Replace Clutch Master/slave cylinders. How much work?
Thread Starter
Pro
Joined: Feb 2003
Posts: 715
Likes: 21
From: Ontario California
Replace Clutch Master/slave cylinders. How much work?
I have come to the conclusion that its time to replace my master and slave cylinders on my 94 coupe..which has 110,000. I have thought about taking it to a shop, but I know it won't be cheap. So I just wondered if this is something you can do in your own garage? I am a little concerned about the skill level and tools needed for such a job, and on the average....if you knew what you were doing...how long would it take?
Since I would be needing parts...what's the better route...GM or aftermarket?
Thanks
Since I would be needing parts...what's the better route...GM or aftermarket?
Thanks
Racer
Joined: Jan 2004
Posts: 286
Likes: 1
From: Madison WI
Not that hard and you don't need any special tools. For the master take out the battery and the kick panel to access the rod connected to the pedal. For the slave it's just two nuts and the line underneath. I've done the slave twice with just rhino ramps. I put in units from Rock auto and have not had any issues with them and they are $50 to $75 compared to GM. I believe every manufacturer has figured out they were putting the piston seal on backwards so that shouldn't be an issue.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
If you're capable of changing/bleeding brake parts, you can do clutch hydraulics. And, it really helps if you're acrobatic enough to get under the dash.
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
I have done it twice on my car, it's not too bad. You'll need a set of metric sockets, and a crows foot wrench to remove the line from the master and the slave. As stated above, just remove the battery and check out under the battery box to make sure there is not corrosion there. You do not need to crawl under the dash; just remove the hush panel and run your hand up the clutch pedal until you find the clip the holds the rod from the master on. Just pop it off w/ a flat edge screw driver, and the rod comes right off. You may have to reuse the same rod, and clip. The clip looks just like the one that holds the cruise control rod to the throttle body.
Make sure you buy the GM fluid, and you should be good to go.
Randy
Make sure you buy the GM fluid, and you should be good to go.
Randy
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
I have done it twice on my car, it's not too bad. You'll need a set of metric sockets, and a crows foot wrench to remove the line from the master and the slave. As stated above, just remove the battery and check out under the battery box to make sure there is not corrosion there. You do not need to crawl under the dash; just remove the hush panel and run your hand up the clutch pedal until you find the clip the holds the rod from the master on. Just pop it off w/ a flat edge screw driver, and the rod comes right off. You may have to reuse the same rod, and clip. The clip looks just like the one that holds the cruise control rod to the throttle body.
Make sure you buy the GM fluid, and you should be good to go.
Randy
Make sure you buy the GM fluid, and you should be good to go.
Randy
with everything minus the GM fluid.....Prestone Dot III from Walmart will do......
Crows foot wrench=line wrenches
One last item, the system is self bleeding, make sure you top off the slave.....put the line on it without letting air in put the line on and fill it with maybe a syringe....then put the M/C in place hook up the line...fill the res....and pump it a few times.....each time you use it it will get better...takes about four good runs
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
with everything minus the GM fluid.....Prestone Dot III from Walmart will do......
Crows foot wrench=line wrenches
One last item, the system is self bleeding, make sure you top off the slave.....put the line on it without letting air in put the line on and fill it with maybe a syringe....then put the M/C in place hook up the line...fill the res....and pump it a few times.....each time you use it it will get better...takes about four good runs
Randy
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Notice I said I replaced my system twice? It died in less then 18 months.I blame the cheap brake fluid I used the first time on the system failing. Well, that and the bad slave. But it also made the master go bad, the fluid was black in that time frame. I think it is a smart investment to use the GM fluid, and so does ZF Doc.
Reason I ask: When the hose and/or rubber components get old, they disintegrate slowly. Your description of black fluid makes me wonder if disintegrating particles were present in your fluid. Those particles are abrasive to the other rubber parts of the clutch hydraulics. It's also why the ZFDoc says to replace everything together.
Caveat: (If you drive a lot of miles, the exception would be if you replace the slave by itself since it's supposed to have half the lift of a master. But, that's in miles -- not age.)
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
When you replaced it the first time, did you replace all 3 components (master, slave, and hose)?YES, everything was brand new.
Reason I ask: When the hose and/or rubber components get old, they disintegrate slowly. Your description of black fluid makes me wonder if disintegrating particles were present in your fluid. Those particles are abrasive to the other rubber parts of the clutch hydraulics. It's also why the ZFDoc says to replace everything together.
Caveat: (If you drive a lot of miles, the exception would be if you replace the slave by itself since it's supposed to have half the life of a master. But, that's in miles -- not age.)My car only gets driven 4 to 6 thousand miles a year.
Reason I ask: When the hose and/or rubber components get old, they disintegrate slowly. Your description of black fluid makes me wonder if disintegrating particles were present in your fluid. Those particles are abrasive to the other rubber parts of the clutch hydraulics. It's also why the ZFDoc says to replace everything together.
Caveat: (If you drive a lot of miles, the exception would be if you replace the slave by itself since it's supposed to have half the life of a master. But, that's in miles -- not age.)My car only gets driven 4 to 6 thousand miles a year.
Last edited by RandyJ75; Jun 24, 2009 at 09:03 AM.
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Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
I dunno man, you could be right, I've just never been one to buy into (and don't take offense) Snake oil.
I'll bet a huge portion of the Nations automotive fleet is running that Yellow Prestone DOT III brake fluid. There is just too many out there running that same stuff and running it for decades....if the fluid was an issue...cars would be crashing all over the place due to fluids.....I know we are talking Clutch...but brake systems are almost the same thing here......
I'll bet a huge portion of the Nations automotive fleet is running that Yellow Prestone DOT III brake fluid. There is just too many out there running that same stuff and running it for decades....if the fluid was an issue...cars would be crashing all over the place due to fluids.....I know we are talking Clutch...but brake systems are almost the same thing here......
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
I have had good luck with brand-name DOT3 and 4 spec fluids over many years.
I have never changed the hose, but have ensured a total flush of the old fluid. My hose is still in good condition and the system works fine; no reason to change it
Sadly, no shop offers a stainless sleeve for these aluminum parts.
Drifting
Joined: Sep 2003
Posts: 1,363
Likes: 7
From: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
If you've ever done brakes and bled brakes, should be simple.
One trick not mentioned so far is getting under the dash to disconnect/reconnect the master shaft is to remove the driver seat (4 bolts and a couple of plugs.
Also, DO USE the GM CLutch fluid -- it is DOT-3 (thinner than DOT-4 which means it will not trap air as easily) and it has both anti-squeal and anti-air-entrapment additives.
Lastly, DO NOT pressure bleed the slave until fully installed -- you can gravity bleed it after connecting to line (i.e. hold it's butt upward and open bleeder until fluid comes out).
HOWEVER, INStall it fully before pressure bleeding -- otherwise damage to the seals WILL occur.
Consider GM or NAPA brand parts (hose is expensive and may be difficult to find).
One trick not mentioned so far is getting under the dash to disconnect/reconnect the master shaft is to remove the driver seat (4 bolts and a couple of plugs.
Also, DO USE the GM CLutch fluid -- it is DOT-3 (thinner than DOT-4 which means it will not trap air as easily) and it has both anti-squeal and anti-air-entrapment additives.
Lastly, DO NOT pressure bleed the slave until fully installed -- you can gravity bleed it after connecting to line (i.e. hold it's butt upward and open bleeder until fluid comes out).
HOWEVER, INStall it fully before pressure bleeding -- otherwise damage to the seals WILL occur.
Consider GM or NAPA brand parts (hose is expensive and may be difficult to find).
Pro
Joined: Jun 2009
Posts: 628
Likes: 0
From: OR
Notice I said I replaced my system twice? It died in less then 18 months.I blame the cheap brake fluid I used the first time on the system failing. Well, that and the bad slave. But it also made the master go bad, the fluid was black in that time frame. I think it is a smart investment to use the GM fluid, and so does ZF Doc.
Randy
Randy
