INT 330 brakes

[Got it]

I replaced friction discs-steel balls and springs but still have no brakes.Have been adjusted to specs.Possible actuators wore too thin?

 

[Janicholson]

The ramps in the expander must be smooth and the balls roll evenly. The pinion support (with the brake flange and the housing, as well as the expander and discs wear. when they do, the angle required to pull on the linkages to top and bottom from the pull clevise becomes wrong and even adjusted tight they don't rotate the expander with force. The following info helps along with roughing all friction surfaces with 250 to 250 grit paper.
The ideal total clearance between the outer housing the outer disk, the outside of the expander the inside of the expander and the outside of the inner disk and the inside of the inner disk and the friction surface of the pinion bearing holder/flange is .030 to .050 inches. this is measured by putting the housing open side up on the work bench (a donut ring around the center cap helps) then placing and centering the outer disc in the housing followed by the expander (where it belongs, collapsed completely and centered) then the inner disc centered on those. A straight edge is placed over the housing edges and feeler gauges (maybe more than one in the fan of blades) is used under the straight edge to measure the clearance all at once. The new disc thickness from All State Ag is about .525 inches. Compute your material removal from there. Toward the spec above. A machine shop can mill or grind the mating edge of the housing to reduce the measured value. Jim

 

[Got it]

Thank you Jim .Another project popped up taking priority over this one so I will definitely do those checks and let you know what I found when I get back to it.

 

[BarnyardEngineering]

Did you break the glaze on the non-replaceable surfaces? The metal surfaces can get very slick.

Also, "adjust to spec" doesn't account for wear and tear. Does it feel like the brakes are applying but nothing is happening, or is the pedal just going to the bottom?

 

[Got it]

It feels like they are applying but very little stopping power

 

[Janicholson]

It feels like they are applying but very little stopping power

This type of brake uses the friction and rotation to add to the expanding/clamping force. This is called a servo action. if geometry and friction combined do not build this force, the servo action will not happen. Proper clearance and scuffed up surfaces will cure it, PTFE spray, like Tri-Flo of it doesn't.used spareingly on splines and balls/grooves is good. lots of it does not work. Jim