KBabcock
True Classic
So I bought my 85 X1/9 and when it was delivered I looked at the carpet where the Master brake cylinder had leaked. I decided my first job would be replacing that Master brake cylinder (MBC). So I started to read and learn then execute. Below is my experience and how I did it along with gotchas you should be aware of.
My first step was planning out the job and the scope of the repair. The MBC was replaced by the previous owner 10 years earlier but the car was never finished as the PO had new living arrangements and health issues which relegated the car to the garage for the next 10 years. Now the brake fluid on the carpet obviously told me something had gone wrong in those 10 years and I needed to replace the MBC. I figured if I am going to pull the pedal box out to replace the MBC a new Master Clutch cylinder would only be $35 dollars more so, it was an easy decision to include that as well. Before I started I read everything I could about the break box, lots of good stuff on this site which will help you out greatly.
So step one was removing the front driver’s seat and steering wheel. The driver seat in the 85’s come out by removing 4 6mm alien head screw from the tracks and lifting it out, easy right? Well I decided to try the front screws first but the seat gets in the way, I needed a short alien head wrench because a normal wrench is too long so I took an old one and cut it down so it would fit. Once the front ones were out I moved the seat forward and the seat slide forward enough to expose the bolts so the back ones came out easy. The rear screws were partially up when I started to remove this. It may be possible to move the seat back far enough to get a normal wrench on the screws if the rear bolts are in all the way.
Next up was removing the steering wheel. This was pretty straight forward and the instruction manual does a good job describing the removal.
Here is a picture of the bolts on the steering column, this will help on later model cars with a safety bold setup on the column which needs to go in a certain way. See red Arrows below.
Now that the area is cleared it time to start removing the box. The first order of business is removing the Flare nuts on the hydraulic lines from both Cylinders, one on the clutch and three on the Brake. Removing these flare nuts is one of the hardest parts of the job and before you even think of starting get the following. 7” Vise Grip 7LW and Kroil (or other high quality penetrating oil). When I first started to try and remove the flare bolt on the Clutch cylinder. I was using a quality set of flare wrench and could feel the bolts starting to stripe. After much research I found the recommend tool was the Vise grip below, obtained mine from MWB. I have a newer car which uses a large flare nut so you may need a smaller one on older cars.
Make sure you have a metal foil pan or other container to catch leaking brake fluid and have rags available. Well I started by trying to remove the Clutch 13mm flare nut and it was as if it was welded on, after several attempts I called it quits for the weekend and started to research ways to get it off. While I was researching I applied some Kriol penetrating oil, (rated one of the best in testing). Did this twice more through the week and come next Saturday I had all the information on how to crack this nut. Before starting the new techniques I thought I would try the vice grips one more time after the Kroil had 5 days to work. It pop right off, I was slack jawed at how easy it came off, all thanks to penetrating oil. Soak your bolts for a few days before doing this project, it makes life so much easier, this was a life saver. The other bolts came off just as easy. The brake flare nuts are 10mm, the vice grip I bought worked on both. Note you only remove the bolts facing down on the bottom, there are some at top of the blocks which can be addressed easily once the box is removed. These blocks that the line screw into exist so you have easy access to remove the flare nuts rather than trying to access them on top which would be impossible. Make sure you break the bottom facing nuts lose before loosen the bolts on the pedal box , it makes life easier again. Use the vice grips and not a Flare wrench, it will save you nuts from rounding…that sounded strange when I proofread it.
Consult your manual on remove because I am skipping some items. Next you want to leave the bolt holding the box to the bulk head on but loose, this allows the box to drop so you can remove the hose clams on the three lines from the fluid reserve under the frunk hood. Pull these hoses off the cylinders, when you do this have a pan to catch the leaking brake fluid and rags handy. Also have something ready to plug the lines before the brake fluid all dribble out, I used some bolts or wooden dulls. Don’t damage the hose. If you spill some brake fluid make sure to wipe it up with Acetone, it will eat your paint.
Remove the bolts and pull the box out, the box is heavy so be ready. Below is my box after being removed. At this point I can see the whole box, as you see it was pretty rusty due to the leaking brake fluid. You can see one of the fluid feeder nipple had broken off which caused the leak. I was also able to move the pedals at this time and noticed they were binding. After reading up on this and realized I had 36 year old grease which undoubtedly had broken down by now. The box needed a full rebuild.
Step one was to mark the remaining hydraulic lines so I knew which order to put them back. Marked them with 1, 2 and 3 lines and take a picture so you can put them back in the correct order. Then remove the lines. I then took off both Master cylinders by removing the two long bolts holding the on. Take pictures because the manual diagrams are not always good and miss things. There is no blown apart diagram of the peddle box which shows how it goes together which I found bizarre so pictures are key.
Pay attention to the angles the brass blocks are at, you will want to put them back in that same position so the hydraulic lines line up properly. Most blocks should be square but mine was on an angle as can be seen in the picture. Again makes life easier.
Pay close attention to the order the washers, spacers and blocks go together. Do not use my pictures as a model on the account the PO put them together in the wrong order but I decided to keep them that way to make lining up the hydraulic lines easier. Again Picture are your friend. Once the Cylinders are off you look like this.
The way the pedals work involves the white plastic shaft. The Brake pedal assembly will pivot on the outside of this shaft while the Clutch pedal will run through the center of this shaft. The shaft should not rotate but if the pedal is frozen it will rotate the Plastic Shaft which will destroy it in time. This shaft needs to come out, cleaned up and re-greased. The next step is removing the spring in the picture above. In this picture I have rotated the pedal beyond the lip of the pedal box. The circular stop on the pedal shaft will catch but you can slip the pedal beyond this lip as shown above. In the normal position this spring is stretched and under a great deal of pressure (See below) moving it to the position in the picture (above) reduces pressure on the spring for removal.
There are a number of ways to get this spring off but I developed this method as an easy and safe way to remove and replace the spring. You will need a metal quick link, some strong rope and a wooden dowel rod. You need to place the quick link on the spring’s end as show in picture.
Then wrap the rope around it as shown below and wrap the other end around the wooden dowel. Put the box on the floor and position your feet so you can hold the box with your feet while you pull the dowel up until the spring disconnects and just move it slightly to the side and gently release pressure. The spring is now free.
Now that the spring is off its time to remove the bolt off the Clutch shaft, this is pretty straight forward. Once the bolt is off you will need to also remove the retaining metal triangle which keeps the Plastic Shaft from rotating needs to come off and is held on by the screw I this picture. Once all off pull the clutch pedal out. (Sorry I didn’t get a picture of this)
Now we need to remove the brake pedal which is far more work. First take the end of the return spring away from the retaining hole so it is loose, this is the spring that wraps around the pedal, it is not strong so safe to deal with. Now you have to push out the plastic shaft starting at the side with the brake pedal. If the grease is still good and the pedal is rotating around this shaft this should be easy. That was not my case, the grease has broken down and the inside of the brake pedal seemed welded to the shaft with rust, yes I know you can’t weld plastic to metal but it was stuck. Other members suggested using a hydraulic press to push this out, great if I had one but I don’t so another plan is needed.
My first though was maybe I can hammer this out but this was greatly discouraged and was informed it would damage the plastic shaft so that was out. What I decided was to use two “C” clamps to push it out. I had some metal bar and cut a piece to place on the plastic shaft and had the C clamps push on that. See picture below. This worked great and allowed me to put the needed pressure on the shaft without damaging it. When I first cranked it down it was not moving so I kept tighten until it broke lose. It sounded like a gun going off, a very sharp crack and it jumped down a few mm. This was a repeated sound as I would apply pressure until it broke loose a few more mm at a time.
You will soon push the shaft level with the brake pedal and will need to cut some pipe to continue to push it out, see below. As you push it further in you will need to change to a longer piece of pipe.
The will take a bit but you will eventually get the shaft out and can then remove the brake pedal and return spring. Now each pedal has a push shaft attached that connects to the Clutch and Brake cylinders. This need to come out so you can re-grease them. I was also going to repaint everything so off they came. This was also a bit of a pain because they are held on with a very small split cotter pin which was rusted in. Getting this out involved a lot of penetration oil, light hammering while holding the pin with needle nose and patients.
The box is now disassembled and you can refinish it as you wish. I wanted to try a process I read about. Using an Apple Cider Vinegar bath to eat the rust away. Hit Walmart for the Vinegar and filled the tub to soak the parts for at least 24 hours after I ground away the rust I could get at. This worked surprisingly well and ate the rust to bare metal and I mean every single gram of rust. Just pitted metal left. Once you pull the part out you need to wash it in a Baking Soda bath to neutralize the acid from the vinegar. Did the same process on some very rusted screws and it returned them to almost new. The only downside is this will eat off any galvanized protection on the part so choose carefully what you will soak.
Once all was clean I reprinted it with rust oleum paint. Then reassembled in reverse order. I used a marine quality silicon grease of a think viscosity. I did this so as not to break down the plastic shaft. Not sure if there is a better choice but this is what I went with. Be liberal with its use and apply to all areas of friction including the return spring. It will help waterproof and protect the Metal.
When reassembling the retraining Metal triangle that fits the slot on the plastic shaft to keep it from rotating was a little striped so I put a dab of epoxy on it to fill the plastic that wore away. This should keep it from rotating but will not really stick to the plastic for future disassembly.
A couple of tips while reassembling.
My first step was planning out the job and the scope of the repair. The MBC was replaced by the previous owner 10 years earlier but the car was never finished as the PO had new living arrangements and health issues which relegated the car to the garage for the next 10 years. Now the brake fluid on the carpet obviously told me something had gone wrong in those 10 years and I needed to replace the MBC. I figured if I am going to pull the pedal box out to replace the MBC a new Master Clutch cylinder would only be $35 dollars more so, it was an easy decision to include that as well. Before I started I read everything I could about the break box, lots of good stuff on this site which will help you out greatly.
So step one was removing the front driver’s seat and steering wheel. The driver seat in the 85’s come out by removing 4 6mm alien head screw from the tracks and lifting it out, easy right? Well I decided to try the front screws first but the seat gets in the way, I needed a short alien head wrench because a normal wrench is too long so I took an old one and cut it down so it would fit. Once the front ones were out I moved the seat forward and the seat slide forward enough to expose the bolts so the back ones came out easy. The rear screws were partially up when I started to remove this. It may be possible to move the seat back far enough to get a normal wrench on the screws if the rear bolts are in all the way.
Next up was removing the steering wheel. This was pretty straight forward and the instruction manual does a good job describing the removal.
- There are 4 screws at the bottom of the plastic steering column cover
- There are then 2 nuts and 2 bolts which need to come off which will allow the column to drop
- Once the column drops you can remove the top piece of Plastic.
- You will have 5 wire plugs which need to be disconnected when this drops, all come apart easily
- Finally you need to undo the joint by the fire wall to remove the column from the spindle, take the bolt completely out as it rides in a grove on the shaft and will not come out if the bolt is in.
Here is a picture of the bolts on the steering column, this will help on later model cars with a safety bold setup on the column which needs to go in a certain way. See red Arrows below.
Now that the area is cleared it time to start removing the box. The first order of business is removing the Flare nuts on the hydraulic lines from both Cylinders, one on the clutch and three on the Brake. Removing these flare nuts is one of the hardest parts of the job and before you even think of starting get the following. 7” Vise Grip 7LW and Kroil (or other high quality penetrating oil). When I first started to try and remove the flare bolt on the Clutch cylinder. I was using a quality set of flare wrench and could feel the bolts starting to stripe. After much research I found the recommend tool was the Vise grip below, obtained mine from MWB. I have a newer car which uses a large flare nut so you may need a smaller one on older cars.
Make sure you have a metal foil pan or other container to catch leaking brake fluid and have rags available. Well I started by trying to remove the Clutch 13mm flare nut and it was as if it was welded on, after several attempts I called it quits for the weekend and started to research ways to get it off. While I was researching I applied some Kriol penetrating oil, (rated one of the best in testing). Did this twice more through the week and come next Saturday I had all the information on how to crack this nut. Before starting the new techniques I thought I would try the vice grips one more time after the Kroil had 5 days to work. It pop right off, I was slack jawed at how easy it came off, all thanks to penetrating oil. Soak your bolts for a few days before doing this project, it makes life so much easier, this was a life saver. The other bolts came off just as easy. The brake flare nuts are 10mm, the vice grip I bought worked on both. Note you only remove the bolts facing down on the bottom, there are some at top of the blocks which can be addressed easily once the box is removed. These blocks that the line screw into exist so you have easy access to remove the flare nuts rather than trying to access them on top which would be impossible. Make sure you break the bottom facing nuts lose before loosen the bolts on the pedal box , it makes life easier again. Use the vice grips and not a Flare wrench, it will save you nuts from rounding…that sounded strange when I proofread it.
Consult your manual on remove because I am skipping some items. Next you want to leave the bolt holding the box to the bulk head on but loose, this allows the box to drop so you can remove the hose clams on the three lines from the fluid reserve under the frunk hood. Pull these hoses off the cylinders, when you do this have a pan to catch the leaking brake fluid and rags handy. Also have something ready to plug the lines before the brake fluid all dribble out, I used some bolts or wooden dulls. Don’t damage the hose. If you spill some brake fluid make sure to wipe it up with Acetone, it will eat your paint.
Remove the bolts and pull the box out, the box is heavy so be ready. Below is my box after being removed. At this point I can see the whole box, as you see it was pretty rusty due to the leaking brake fluid. You can see one of the fluid feeder nipple had broken off which caused the leak. I was also able to move the pedals at this time and noticed they were binding. After reading up on this and realized I had 36 year old grease which undoubtedly had broken down by now. The box needed a full rebuild.
Step one was to mark the remaining hydraulic lines so I knew which order to put them back. Marked them with 1, 2 and 3 lines and take a picture so you can put them back in the correct order. Then remove the lines. I then took off both Master cylinders by removing the two long bolts holding the on. Take pictures because the manual diagrams are not always good and miss things. There is no blown apart diagram of the peddle box which shows how it goes together which I found bizarre so pictures are key.
Pay attention to the angles the brass blocks are at, you will want to put them back in that same position so the hydraulic lines line up properly. Most blocks should be square but mine was on an angle as can be seen in the picture. Again makes life easier.
Pay close attention to the order the washers, spacers and blocks go together. Do not use my pictures as a model on the account the PO put them together in the wrong order but I decided to keep them that way to make lining up the hydraulic lines easier. Again Picture are your friend. Once the Cylinders are off you look like this.
The way the pedals work involves the white plastic shaft. The Brake pedal assembly will pivot on the outside of this shaft while the Clutch pedal will run through the center of this shaft. The shaft should not rotate but if the pedal is frozen it will rotate the Plastic Shaft which will destroy it in time. This shaft needs to come out, cleaned up and re-greased. The next step is removing the spring in the picture above. In this picture I have rotated the pedal beyond the lip of the pedal box. The circular stop on the pedal shaft will catch but you can slip the pedal beyond this lip as shown above. In the normal position this spring is stretched and under a great deal of pressure (See below) moving it to the position in the picture (above) reduces pressure on the spring for removal.
There are a number of ways to get this spring off but I developed this method as an easy and safe way to remove and replace the spring. You will need a metal quick link, some strong rope and a wooden dowel rod. You need to place the quick link on the spring’s end as show in picture.
Then wrap the rope around it as shown below and wrap the other end around the wooden dowel. Put the box on the floor and position your feet so you can hold the box with your feet while you pull the dowel up until the spring disconnects and just move it slightly to the side and gently release pressure. The spring is now free.
Now that the spring is off its time to remove the bolt off the Clutch shaft, this is pretty straight forward. Once the bolt is off you will need to also remove the retaining metal triangle which keeps the Plastic Shaft from rotating needs to come off and is held on by the screw I this picture. Once all off pull the clutch pedal out. (Sorry I didn’t get a picture of this)
Now we need to remove the brake pedal which is far more work. First take the end of the return spring away from the retaining hole so it is loose, this is the spring that wraps around the pedal, it is not strong so safe to deal with. Now you have to push out the plastic shaft starting at the side with the brake pedal. If the grease is still good and the pedal is rotating around this shaft this should be easy. That was not my case, the grease has broken down and the inside of the brake pedal seemed welded to the shaft with rust, yes I know you can’t weld plastic to metal but it was stuck. Other members suggested using a hydraulic press to push this out, great if I had one but I don’t so another plan is needed.
My first though was maybe I can hammer this out but this was greatly discouraged and was informed it would damage the plastic shaft so that was out. What I decided was to use two “C” clamps to push it out. I had some metal bar and cut a piece to place on the plastic shaft and had the C clamps push on that. See picture below. This worked great and allowed me to put the needed pressure on the shaft without damaging it. When I first cranked it down it was not moving so I kept tighten until it broke lose. It sounded like a gun going off, a very sharp crack and it jumped down a few mm. This was a repeated sound as I would apply pressure until it broke loose a few more mm at a time.
You will soon push the shaft level with the brake pedal and will need to cut some pipe to continue to push it out, see below. As you push it further in you will need to change to a longer piece of pipe.
The will take a bit but you will eventually get the shaft out and can then remove the brake pedal and return spring. Now each pedal has a push shaft attached that connects to the Clutch and Brake cylinders. This need to come out so you can re-grease them. I was also going to repaint everything so off they came. This was also a bit of a pain because they are held on with a very small split cotter pin which was rusted in. Getting this out involved a lot of penetration oil, light hammering while holding the pin with needle nose and patients.
The box is now disassembled and you can refinish it as you wish. I wanted to try a process I read about. Using an Apple Cider Vinegar bath to eat the rust away. Hit Walmart for the Vinegar and filled the tub to soak the parts for at least 24 hours after I ground away the rust I could get at. This worked surprisingly well and ate the rust to bare metal and I mean every single gram of rust. Just pitted metal left. Once you pull the part out you need to wash it in a Baking Soda bath to neutralize the acid from the vinegar. Did the same process on some very rusted screws and it returned them to almost new. The only downside is this will eat off any galvanized protection on the part so choose carefully what you will soak.
Once all was clean I reprinted it with rust oleum paint. Then reassembled in reverse order. I used a marine quality silicon grease of a think viscosity. I did this so as not to break down the plastic shaft. Not sure if there is a better choice but this is what I went with. Be liberal with its use and apply to all areas of friction including the return spring. It will help waterproof and protect the Metal.
When reassembling the retraining Metal triangle that fits the slot on the plastic shaft to keep it from rotating was a little striped so I put a dab of epoxy on it to fill the plastic that wore away. This should keep it from rotating but will not really stick to the plastic for future disassembly.
A couple of tips while reassembling.
- When you put the box back in only put the bolts on the bulk head back on at first and keep them very loose so the box can move, this will help to alien the flare nuts on the hydraulic lines.
- Clean the flare nuts and brass blocks very well so there is no grim on the threads, makes life easier.
- Put a box under the pedal box until you are ready to secure it to hold it up.
- Put a small dab of anti-seize on the flare nuts.
- When putting the flare nuts on tighten them first by hand so as not to cross thread them in the brass blocks.
- Replace the Brake Reservoir lines, I cheaped out and didn’t which I now regret. It will run you $70 but is worth it. Install the lines before installing the pedal box. Also make sure you use break line 5mm to 6mm internal diameter
