DSMTalk Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum banner

1 - 1 of 1 Posts

Senior Moderator
3,398 Posts
Discussion Starter #1
I recently replaced my master cylinder as preventative maintenance. It's easy and I've read about people paying shops to do this. Which is a shame. This will take a expert dsm'er less then an hour tops and an novice mechanic a sunday afternoon. So i snapped some pics and will make a quick writeup about it.
I'm not going to go into bleeding the slave cylinder. It's literally 1 10mm bleeder valve and some clutch pedal pumping.
Parts and tools required.

1. New master cylinder
2. brake fluid
3. empty liquid container(a 12oz soda bottle will cover it)
4. small tubing, vacuum hose size, used for bleeding
5. car jack and jack stands
6. 10mm and 12mm flare wrench, I wouldn't skip on this
7. Basic socket set will suffice(with extensions)
8. pliars
9. 10mm box wrench to bleed the slave cylinder after
10. drip pan to catch extra crap
11. Flash light for under the dash fun

Step 1: Disconnect the car battery(of course)
Step 2: Safely jack up the car. with a floor jack I just jack from the front cross member and rest the car on two sturdy jacks. I put the jacks under two of the supports where the suspension bolts to the body
Step 3: Put the box end of a 10mm wrench on the bleeder valve of the slave and break it free. Leave the wrench on there and slide the tubing over the nipple and put the other end in your bottle, set the bottle in the drip pan for when I knock it over later(I always do, hence the drip pan.) Take the cap off the master cylinder and pump the clutch pedal to flush out all the old brake fluid!

Step 4: Let's get under the dash, this part sucks if you are over 4'11. Unless you are really skinny, and still it will suck. I put the seat all the way back and slide under the dash at an angle, half hanging out the door. So the top of my head is hitting the pedals and i have two arms free to get up in there as much as possible. When you do this, get your flashlight and you should be able to see all kinds of cool shit, including your master cylinder. The master is mostly held in by two 12mm nuts. one under the dash and one under the hood. The push rod attatches to the pedal with a solid metal bushing and a cotter pin.

Step 5: Use a 12mm socket to remove the first nut(easy).

Step 6: Now, depending on how your master cylinder is adjusted, it may be putting some pressure on the bushing that holds the C bracket to the pedal assembly. I used a 12mm flare wrench to loosen up the adjustment lock nut and i rotated the rod until the bushing was easy to slide back and forth in the bracket.

Step 7: Grab some pliars get up in there and get that cotter pin out. It's a wierd one too, you have to grab the end, twist and pull. Don't worry about breaking it, if you do, you can replace it with any old cotter pin. After you yank that s.o.b out youll probably hit your hand and need a bandaid. Either way, you're done under the dash. Like most dsm stuff, getting the old stuff out is the hard part.

Step 8: Back under the hood. We need to finish disconnecting the master cylinder. This is accomplished by removing the primary master cylinder reservoir which is bolted to the firewall by two 10mm bolts. Put the cap back on the reservoir so whatever fluid is left doesn't splash into your eyes or ruin your paint and remove these two bolts.

Step 9: Then with a pair of pliars, remove the squeeze clamp from the master cylinder side of the feed hose(the hose that goes from the reservoir to the top of the master cylinders built-in reservoir.

Step 10: Now this part may be tricky. I didn't have a problem getting the flare wrench fully on the nut, but I don't have a/c either. You need to break free the nut and it may be pretty hard to get loose. I busted my finger doing this. If you cant get the flare wrench fully seated, keep trying till you do. Unbolt the power steering lines if you have to or slide stuff out of the way, whatever works.

Step 11: Now only one more nut stops you, and it's easy. Pop that sucker free, becarefull not to drop the nut into the engine bay. you may want to finish unscrewing it by hand to ensure this. Getting this nut back on is a pita but if you do lose it, you can get another at lowes or home depot(bring the remaining nut to get the correct size.)

Step 12: Remove the master, yay! Installation of the new part is easier except getting the 12mm nut back onto the stud on the master cylinder under the hood. Leave the slave bleeder open and fille the reservoir and pump. repeat until the system is filled up, then bleed however you like too. Do a search if you don't know how it's been spoken of a million times.
1 - 1 of 1 Posts