D4D Clutch Master Cylinder Replacement step by step
Posted: Tue May 29, 2012 12:09 pm
Hi Guys
Over time I started to realise that changing gears on my lux started getting more and more “notchy”. I also noticed that it is more and more difficult to put it in gear when stationary. If I pumped the pedal once or twice the issue would go away. Occasionally I would also hear a squeak when I depress the clutch but it was not a spring or mechanical noise. More like a “fluid” noise. (I am not quite sure how to explain it.) So on Sunday I decided to bleed the clutch hydraulic system only to find that I cannot get the air out. The more I bled it the more air seemed to be introduced.
I considered the situation and narrowed it down to the master cylinder, considering the above, as well as that this is the only part moving when you are bleeding the system. There was also no seepage on the slave cylinder which normally is a good indicator that there may be a problem there. I inspected the master cylinder and found no leakage on the inside. So yesterday I got on the phone and started looking for a solution.
I discovered that the master cylinder is a sealed unit so one cannot get a seal kit and refurbish the cylinder yourself. I also discovered that it is made of plastic so it is unlikely that you can hone it again. I am going to try and open one to see how it works and what can actually be done. I also found that your “normal” parts distributors do not even list the master cylinder yet. They do however list a seal kit for the slave cylinder. At Toyota the cost of the master cylinder is just over a R1000. They also sell a seal kit for the slave cylinder which costs just over R300. I found a company that specialises in Toyota spares and they quoted R380 for the master cylinder. I went there and found that they only had stock of the master cylinder for the Quantum. It differs slightly from the Hilux one. The guy could order me one but it would take a day or two and I could not wait so I thought I would have to get one from the dealers. He then went and checked and found a second hand one off a Hilux. I tested it and it seemed ok so I thought I would give it a try for R100.
This is the process of replacing the master cylinder:
The clutch hydraulic system does not have its own dedicated brake fluid reservoir as is often the case but shares the reservoir with the brake system. The feed from the reservoir is located on the right hand side when viewed from the front of the vehicle.
This is the location of the master cylinder.
Here is the outlet from the Reservoir leading to the clutch master cylinder.
This is the location of the master cylinder. I removed the intercooler cover to get easier access to the master cylinder as it is slightly in the way. Because I was going to remove these pipes (arrows) and did not want any brake fluid to spill inside the engine bay I decided to drain the fluid from below. i.e. from the clutch slave cylinder.
Actually if you work carefully the spillage from the reservoir is minimal, provided you have a way of blocking the feed pipe from the reservoir or if you have the new master cylinder ready to quickly swap the pipe over whilst pinching the pipe with your fingers to prevent brake fluid spilling out. You do not want the brake fluid to come in contact with any paint.
I have devised a system of sucking out brake fluid that is very handy especially if you are trying to bleed a system that is completely dry and do not feel like pumping for hours to get a drop of fluid in the pipes. I will post some pics in a separate thread. I drained the fluid through the salve cylinder which is located on the left hand side of the gearbox when viewed from behind and is easily accessible from underneath the vehicle.
Then undid both the pipe feeding from the reservoir and the high pressure line going to the slave cylinder. It takes a size 10 spanner. The clamp on the feed hose is easily compressed and moved back.
The next step was to undo the master cylinder inside the cabin. Space is very cramped in the foot well so it was difficult to take good pictures of the links etc. I did take some pics of the pin outside which will help to understand how to remove the pin.
First I had to detach the master cylinder push rod from the clutch pedal. This is easily achieved by pulling out the split pin which secures the clutch pedal pin and then pushing out the pin itself. This is the best I could do. Here is the split pin (red arrow) and the pin (black arrow) which needs to be removed. Sorry for the poor quality of the pic but it is difficult to take in that position.
Here is what the pin assembly looks like. I find it easier to remove something once I have seen what it looks like so I took these pics for your benefit.
The next step was to undo the two nuts holding the master cylinder in place. (black arrows) They take a size 12 spanner and have long studs protruding so those long sockets would work very well. (I have subsequently discovered that a standard length 12mm Gedore socket fits on the nut so it is actually very easy to remove these nuts using a long extension and a universal connection.) The nut on the top left is the hardest to get to and turn. There is little space to swing a spanner if you do not want to loosen the harness to the left of the nut. (yellow arrow) The hole in the clutch pedal through which the pin must go is also clearly visible. (red arrow)
The master cylinder is then quite easily withdrawn from the inside of the engine bay.
To install the replacement cylinder is just as simple. What I like to do is to put the cylinder in place and then I first screw in the pipe fitting. It is easier to make sure that you screw it in correctly and that you do not cross thread it when the cylinder is still loose and can be tilted. I made sure that I could screw it in quite easily and screwed it in all the way but did not tighten it yet as it is easier to feel how tight it is once the cylinder is bolted down securely.
Getting everything back on inside the cab can be very frustrating due to the limited space but did not take all that long and did not need a single swear word.
Then I tightened the pipe fitting and fitted the rubber hose feeding the cylinder from the reservoir.
The next step was to bleed the system. First I filled the reservoir with brake fluid and used my vacuum system to suck the fluid into the system quickly. Then my trusty assistant and I bled the system as normal. When there is no back pressure on the pedal due to the bleeding process the pedal will stay down on the floor so it is the easiest to operate the pedal by hand as you need to physically pull it back after every stroke.
The air bled out quickly and the clutch has a great feel to it again. A 100 Rand well spent!
Over time I started to realise that changing gears on my lux started getting more and more “notchy”. I also noticed that it is more and more difficult to put it in gear when stationary. If I pumped the pedal once or twice the issue would go away. Occasionally I would also hear a squeak when I depress the clutch but it was not a spring or mechanical noise. More like a “fluid” noise. (I am not quite sure how to explain it.) So on Sunday I decided to bleed the clutch hydraulic system only to find that I cannot get the air out. The more I bled it the more air seemed to be introduced.
I considered the situation and narrowed it down to the master cylinder, considering the above, as well as that this is the only part moving when you are bleeding the system. There was also no seepage on the slave cylinder which normally is a good indicator that there may be a problem there. I inspected the master cylinder and found no leakage on the inside. So yesterday I got on the phone and started looking for a solution.
I discovered that the master cylinder is a sealed unit so one cannot get a seal kit and refurbish the cylinder yourself. I also discovered that it is made of plastic so it is unlikely that you can hone it again. I am going to try and open one to see how it works and what can actually be done. I also found that your “normal” parts distributors do not even list the master cylinder yet. They do however list a seal kit for the slave cylinder. At Toyota the cost of the master cylinder is just over a R1000. They also sell a seal kit for the slave cylinder which costs just over R300. I found a company that specialises in Toyota spares and they quoted R380 for the master cylinder. I went there and found that they only had stock of the master cylinder for the Quantum. It differs slightly from the Hilux one. The guy could order me one but it would take a day or two and I could not wait so I thought I would have to get one from the dealers. He then went and checked and found a second hand one off a Hilux. I tested it and it seemed ok so I thought I would give it a try for R100.
This is the process of replacing the master cylinder:
The clutch hydraulic system does not have its own dedicated brake fluid reservoir as is often the case but shares the reservoir with the brake system. The feed from the reservoir is located on the right hand side when viewed from the front of the vehicle.
This is the location of the master cylinder.
Here is the outlet from the Reservoir leading to the clutch master cylinder.
This is the location of the master cylinder. I removed the intercooler cover to get easier access to the master cylinder as it is slightly in the way. Because I was going to remove these pipes (arrows) and did not want any brake fluid to spill inside the engine bay I decided to drain the fluid from below. i.e. from the clutch slave cylinder.
Actually if you work carefully the spillage from the reservoir is minimal, provided you have a way of blocking the feed pipe from the reservoir or if you have the new master cylinder ready to quickly swap the pipe over whilst pinching the pipe with your fingers to prevent brake fluid spilling out. You do not want the brake fluid to come in contact with any paint.
I have devised a system of sucking out brake fluid that is very handy especially if you are trying to bleed a system that is completely dry and do not feel like pumping for hours to get a drop of fluid in the pipes. I will post some pics in a separate thread. I drained the fluid through the salve cylinder which is located on the left hand side of the gearbox when viewed from behind and is easily accessible from underneath the vehicle.
Then undid both the pipe feeding from the reservoir and the high pressure line going to the slave cylinder. It takes a size 10 spanner. The clamp on the feed hose is easily compressed and moved back.
The next step was to undo the master cylinder inside the cabin. Space is very cramped in the foot well so it was difficult to take good pictures of the links etc. I did take some pics of the pin outside which will help to understand how to remove the pin.
First I had to detach the master cylinder push rod from the clutch pedal. This is easily achieved by pulling out the split pin which secures the clutch pedal pin and then pushing out the pin itself. This is the best I could do. Here is the split pin (red arrow) and the pin (black arrow) which needs to be removed. Sorry for the poor quality of the pic but it is difficult to take in that position.
Here is what the pin assembly looks like. I find it easier to remove something once I have seen what it looks like so I took these pics for your benefit.
The next step was to undo the two nuts holding the master cylinder in place. (black arrows) They take a size 12 spanner and have long studs protruding so those long sockets would work very well. (I have subsequently discovered that a standard length 12mm Gedore socket fits on the nut so it is actually very easy to remove these nuts using a long extension and a universal connection.) The nut on the top left is the hardest to get to and turn. There is little space to swing a spanner if you do not want to loosen the harness to the left of the nut. (yellow arrow) The hole in the clutch pedal through which the pin must go is also clearly visible. (red arrow)
The master cylinder is then quite easily withdrawn from the inside of the engine bay.
To install the replacement cylinder is just as simple. What I like to do is to put the cylinder in place and then I first screw in the pipe fitting. It is easier to make sure that you screw it in correctly and that you do not cross thread it when the cylinder is still loose and can be tilted. I made sure that I could screw it in quite easily and screwed it in all the way but did not tighten it yet as it is easier to feel how tight it is once the cylinder is bolted down securely.
Getting everything back on inside the cab can be very frustrating due to the limited space but did not take all that long and did not need a single swear word.
Then I tightened the pipe fitting and fitted the rubber hose feeding the cylinder from the reservoir.
The next step was to bleed the system. First I filled the reservoir with brake fluid and used my vacuum system to suck the fluid into the system quickly. Then my trusty assistant and I bled the system as normal. When there is no back pressure on the pedal due to the bleeding process the pedal will stay down on the floor so it is the easiest to operate the pedal by hand as you need to physically pull it back after every stroke.
The air bled out quickly and the clutch has a great feel to it again. A 100 Rand well spent!