How the clutch brake actually works.

The clutch brake actually clamps around the input shaft of the transmission. It has 2 small tabs, one on each side that fit into the splines on the shaft. When one depresses the clutch pedal all the way while rolling, the tabs break off rendering the brake inoperative.

 

The clutch brake sits between the clutch and the transmission. As the other poster stated, there are a couple tabs to keep it from spinning. You can access it from the plate directly on the bottom of the bell housing where you will find the throw out bearing grease point. If you can spin it by hand, it is shot. Some are one piece units, but replacements are two piece split units that resemble half round puzzle pieces.

You need a small roll punch to remove them, split them apart and remove each half. There are small holes where the roll pins lock the pieces together.

I'm not 100% sure how it works because I haven't seen it in action, but I have seen them replaced, and I have done adjustments on the clutch itself.

 

It is located between the release bearing and the front of the transmission. Depressing the clutch pushes the release bearing back towards the front of the transmission on the input shaft. This 'stops' the shaft allowing you to get the trans in gear. Properly adjusted- the clutch pedal should remain approx. 1/2" off the floor when fully depressed.

 

I may be wrong but clutch break is between clutch and transmission. There is a faceplate on tranny that clutch brake presses against to stop. There are one piece and two piece brakes. One piece can be torched out through inspection hole but not fun. Usually results in sparks in eyes and burned face. Think I'd almost rather pull tranny. But on piece can be cut out and replaced with two piece without pulling transmission

 

You can find a couple videos on YouTube on clutch brakes. I wasn't even aware that there was a hinged split type. Now I understand more about how a heavy clutch works. It's totally opposite the clutch on a passenger vehicle. A passenger unit is pushed toward the flywheel to release it and a heavy truck clutch is pulled to disengage.

You learn as you go, I guess.

 

Do not ever push the clutch pedal all the way to the floor while moving. It will burn out the clutch brake and need to be replaced so you can put the trans in gear when stopped with out grinding gears.

 

its a wear item, like brake pads or the clutch itself, but you can minimize it's use with better driving habits to prolong its life. Try not to throw the transmission in neutral to coast to a stop like in a car...you'll be using the clutch brake at every red light to get set to take off, which will trash it prematurely.