Bloody Brakes

Apr 19, 2014

RAY: This was sent by a guy named John Tomasetti. He says this is a real-life situation. He has a 1982 Jeep CJ7, and it had sticky front-brake calipers. "So," he said, "I bought the rebuilding kits for both front wheels and proceeded to rebuild the calipers myself. The rebuilding kits included all the necessary o-rings and dust boots, as well as new steel pistons to complete the job. I proceeded to rebuild both of these front calipers, feeling good that I had no spare parts left over. I was satisfied that I did the rebuild job correctly, and, in fact, that my work was flawless.

“However," he goes on, "when I finished the job, I couldn't seem to bleed the brakes properly. The pedal went to the floor as if there were air trapped in the system. I must have bled a gallon of brake fluid through the system to no avail, but there were no leaks. Finally, I took the Jeep to a shop, and, using their professional equipment, they bled them -- to no avail."

TOM: Wow!

RAY: Finally they say, "You need a new master cylinder." They, what? Replaced the master cylinder three times to no avail. They checked the lines, they checked the rear brakes -- everything in perfect condition. They gave up.

TOM: Wow! Now what? I'm awed!

RAY: After five days, three more master cylinders, and many more gallons of brake fluid, he takes the thing to the Jeep dealer. They bleed the brakes, they put in master cylinders, they do all this and, finally, someone figures it out, and it cost no money to get it fixed. So, what did they do?

RAY: John rebuilt both calipers. In other words, he put them on his dining room table, took them all apart, installed the new kits that he had -- flawlessly, I might add -- and reinstalled them. But in doing so, he put the left one on the right and the right one on the left, and by making that mistake, the bleeder -- that is, the little valve you open to let air escape from the system -- was at the bottom of each caliper, because he had flipped them around, and not at the top where, what?

TOM: The air goes.

RAY: The air is. If you take a liquid that has air in it too, and you flip it upside down, no matter what you do, the air always goes to the top.

TOM: You can try this out with a bottle of orange soda. Which we do every week here.

RAY: And no matter how much bleeding you do, there is so much air, which is compressible, trapped in the system, that you cannot get a brake pedal no matter how many master cylinders you put in. So who's our winner this week?

TOM: The winner is Lu Shirley from Papillon, Nebraska. Congratulations!

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