KB5 MC & Brake Lines

Got under the truck today and took a look at the Master Cylinder to compare it to the original one that came with the truck. I noticed that only the front brakes are hooked up. I knew the previous owner had redone the front brakes and said he did not get to the rears. I thought they were still hooked up, but needed to be worked. Wrong, they are not hooked up to the MC - which explains the "hard to stop" condition.

I took a pic of the MC which is presently on the KB5. Then the other pic is of the brake junction block with the lines going to the fronts and a plug inserted where I assume the rear line will tap into. I also noticed that the straight line which comes off the MC to the junction block is larger in diameter than the brake lines coming out of the junction block and going to the wheels.

The K/KB shop manual has no diagram of the brake line routing nor line size - in the case of the larger/smaller lines I have. The rear brake lines are still on my truck, but very rusty. Can't see where they come out under the cab and go to the brake block - probably twisted/rotted off at this point. I will replace them and the rubber line on the rear axle.

My plan is to send the original MC out for rebuilding by a qualified rebuilder. Suspect I may have to send out the rear wheel cylinders as well.

So take a look and tell me what you think. Are the line sizes correct? Does the brake block look somewhat correct?

New master cylinders are available from Raybestos.

New master cylinders are available from Raybestos.

Thanks, I saw them and knew I could get a new one if needed. My reason for using my original is that the MC cap off the original will most likely not fit on the Raybestos MC. I want to use the Brake Fluid reservoir tank/set-up that is original to my truck. Take a look under the post, "1948 KB5 - What is it?"

on your lines, USUALLY there is one larger diameter line from master which goes to a junction block at left front wheel, this block is attached to inside end of rubber brake line by a threaded hollow bolt, the supply line goes into that bolt, the jumper line from left front wheel to right front wheel comes out of front of junction block, the rear wheels line comes out rear of junction block,

looks like yours has been heavily modified,

on your lines, USUALLY there is one larger diameter line from master which goes to a junction block at left front wheel, this block is attached to inside end of rubber brake line by a threaded hollow bolt, the supply line goes into that bolt, the jumper line from left front wheel to right front wheel comes out of front of junction block, the rear wheels line comes out rear of junction block,

looks like yours has been heavily modified,

Ok, I think I got it. My concern was the larger diameter line coming off the master - which I have. I guess the former owner just used a contemporary brake block to feed the front brake lines much like a "newer" car would. I know the steel lines are correct in size as I still have the one going to the rear in place, but very rusty. Whoever did the brake lines bought a length of line that was too long and thus the loop-around you see - not too pretty. I will neaten this up. I have the know how/tools to make my own brake lines so I will clean the whole thing up and add the rear line to the junction block.

The former owner said he re-did the front brakes. He installed new wheel cylinders and I have the old ones with the truck. I don't know anymore than that as I don't know if he put on new shoes or had them relined or what condition the drums are in, but it does stop with some effort seeing it has no rear brakes.

Thanks for your reply, helps me out.