When to replace the hub on drum brake shoes?
When to replace the hub on drum brake shoes?
The hub stays in place when the linings are changed. Shoes with bonded lining should, for safety, be replaced when the lining is worn to & 1/10 in. (3 mm) thick, even if a minimum thickness of 1/16 in. (1.5 mm) is quoted in the car handbook.
Why are my brake shoes square with the drum?
The shoe lands or “bosses” are an often overlooked item when looking for the cause of a rear wheel lockup condition. The shoe lands keep the brake shoes square with the drum and provide a friction surface for the shoes to move against.
What causes rear wheel lockup on Phoenix brakes?
The shoe lands or “bosses” are an often overlooked item when looking for the cause of a rear wheel lockup condition. The shoe lands keep the brake shoes square with the drum and provide a friction surface for the shoes to move against. Over time the bosses can become grooved and corroded as in Figure 61.6.
What causes rear drum brakes to engage too soon?
If the parking brake system is not de-adjusted properly before the brake shoes are adjusted it will cause the rear brakes to engage too soon. This is especially true of vehicles equipped with duo-servo rear drum brakes (see Figure 61.1).
Where are the drum brakes on a bicycle?
Drum brakes are popular on utility bicycles in countries with wet weather; much less so for recreational and racing use, where rim brakes predominate and disc brakes are becoming more popular. A drum brake may be an integral part of a hub, or may thread onto the left side of the hub the same way a freewheel threads onto the right side.
How are brake shoes bonded to brake drums?
Linings may be riveted or bonded to the brake shoes. With riveted linings, replace the shoes well before the lining wears down to the level of the rivet heads. Exposed heads score and ruin the brake drums.
Where are the spoke holes in drum brakes?
Drum-brake shoe assemblies are proprietary. Most drum brakes have the spoke holes at the outside of the drum, and the large spoking diameter requires special attention when building a wheel, in particular, a low cross number if a small-diameter rim is used.
Where are the forward shoes on drum brakes?
The shoe located at the rear of the assembly. Many people have mistakenly assumed that since the front brakes supply most of the car’s stopping force, the forward shoes on drum brakes do most of the work. No. Next, when you start disassembling everything, don’t use pliers or vise grips. Brake tools are inexpensive, and will prevent injury.
Where are the brake drums on a car?
Return springs retract the shoes after brake application. The brake drum mounts on the axle or wheel hub, and some drums incorporate the hub. Most brake drums are made of solid cast iron, but there are also steel and aluminum drums with cast iron liners.
The hub stays in place when the linings are changed. Shoes with bonded lining should, for safety, be replaced when the lining is worn to & 1/10 in. (3 mm) thick, even if a minimum thickness of 1/16 in. (1.5 mm) is quoted in the car handbook.
What makes a drum brake work like a lever?
But the primary shoe is anchored into place by the stationary wheel cylinder. So the driving force from the secondary shoe wedges the primary shoe much tighter into the brake drum. A very clever design, it multiplies force like a lever does. Drum brakes that incorporate that feature are called self-actualizing brakes.
