Section I: Master Cylinder Replacement

 

LJ brakes leave a lot to be desired. Like being able to stop the little sucker. Suzuki got a lot of things right when they made the LJs, but all of the competent engineers must have been on vacation when the brakes were designed. The master cylinder has a very small volume and a limited reservoir. The drum brakes are small, very soft and wear quickly. They must be kept very well adjusted or the master cylinder does not have the volume to fully apply the brakes with one pedal stroke. But we can fix this. Yes, we can.

 

Suzuki finally discovered what decent brakes were and put them on their SJ413 Samurai. This braking system can be used to upgrade the LJ with relative ease. At least I thought it was pretty easy. Before the wheel brakes are upgraded, I believe that it is necessary to upgrade the master cylinder first. So let’s do that little project.

 

PARTS:

  1. SJ413 Master cylinder. These are available from a number of sources: Ebay, Junkyards, etc. I got mine from Ebay for $10, I think.
  2. Approx. 40” of 3/16” brake line from an auto parts store and two metric nuts for it. I have lots of old brake line pieces lying around, so I just took a couple of nuts from those.
  3. A rubber brake hose. This can be the rear brake hose from an SJ413 or a spare front brake hose from an LJ. If you’re going to upgrade the wheel brakes after the master cylinder is complete, then you can just use one of your front brake hoses. These are ideal, as you’ll see later.
  4. A piece of 1 ¼” x 1/8” metal about 2” long.
  5. A 5/16” nut.
  6. A way to plug a brake line connection. The method I use is to cut an old brake line about a ½” away from the nut with a pair of wire cutters. Then I weld the cut end shut. I think you could maybe use a brass 1/8” pipe plug too. I’ll check on that.

 

Special Tools:

  1. 10mm brake line wrench. Indispensable. Available at any auto parts store.
  2. Brake line double flaring tool. Brake line flares are special and you need this tool to do them. Available at Harbor Freight, Auto parts stores, etc. You may even be able to borrow or rent them from some auto parts stores.
  3. Rotary grinding device. Die grinder, Dremel, or drill with a burr bit. I guess you could use a rat-tail file if you have a week to spend on it.
  4. Drill and a hand full of bits.
  5. Some way to bend 3/16” brake line. I’ve got my old benders for ¼” copper that do a good job. I think you can get a cheap bender at Wal-Mart. Steel brake line is very forgiving, you can even bend it pretty well with your bare hands as long as you’re careful.

 

That’s all I think you need other than your standard hand tools, So let’s get started.

 

 

There’s the old master cylinder. What a mess. Looks hard to get to.

 

 

Well, get everything out of the way so we can work on it. That’s much better

 

 

The first thing we need to do is get under the dash and remove the clevis pin that holds the push rod to the brake pedal. Just take out the cotter pin and it should come out easily.

 

 

Now we need to use that dandy little brake line wrench and take the brake line off the master cylinder. OOPS! Dangit. Just my luck. Now I need TWO 40” pieces of 3/16” brake line. Oh well, we’ll deal with that later.

 

 

Now we take out the two bolts holding the master cylinder to the firewall. 12mm wrench. Don’t curse too loud, you’ll wake up the mice living under the seat.

 

 

Now it’s time to get the SJ413 master cylinder prepared. I hope yours is in better shape than mine was.

 

 

 

Got to get it off of that booster. Take off the two nuts and gently lift it off. Yeah, right. It took two screwdrivers and a little work to get mine off.

 

 

Page 2 of the section 1

 

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