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What To Look For In Trailer Brakes

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Around three quarters of trailers that have hydraulic brakes fail tests by dealers and a quarter do not have any stopping power at all.

Ofttimes, they are portrayed as the solution to all of our problems with braking Air-activated anchors have an equally bad track history – much of it due to the lack of maintenance and adjustments.

Simple things can be performed to determine the issue and modify the trailer brakes so that they get in the right direction.

We sought advice by Dave White, service manager at Lincolnshire trailer hire and sales expert Ireland’s Farm Machinery.

He discusses the best way you can test the brakes on your vehicle, upgrade parts and costs.

In the experience of Mr. White, numerous brakes do not comply with safety standards.

He adds: “When we started out using the brake-testing kit from Bagma, we discovered that the majority of trailers operating on standard Ag-Spec eight-stud axles failed to reach the minimum brake efficiency.

“And with air brakes , it’s usually worse since they have to be able to operate at the efficiency of 45. As with many farm trailers our fleet of hire vehicles sits still throughout the time, and drums are prone to rust because of lack of usage.

“We must be certain that the trailers are in good condition before they leave, and therefore, we have a easy process that we follow to make sure they’re ready to go out on the road.”

Preparation for testing

Before anything passes through Bagma test at Ireland’s The brakes are checked for adjustment, and slack-adjusters are turned up or splined levers are wound around and re-positioned onto their shafts.

Before you test, tighten the slack-adjusters tight, and then lower them one quarter turn or more if your brakes aren’t yet binding.

The test

Bagma and Turnkey have come up with an electronic brake tester that does not require a special tool to operate , other than the standard BrakeSafe box, which is situated on the floor of the tractor’s cabin.

A decelerometer is a device that determines the force that comes to play when anchors are pressed.

When you connect the trailer’s brake line through an spool valve, it is possible to determine the efficiency of the brakes on the trailer, without affecting the tractor.

The oil that comes from the spool valve typically with a higher pressure than that which flows through the brake lines , therefore restrictor valves as well as a pressure gauge can be employed to offer an accurate braking force.

Once you’ve plugged the trailer’s brake line into a spool valve, it’s now possible to gauge the effectiveness of braking on that trailer.

Once the brakes are plowed into the tester box installed in your cab simple to set off at a steady speed (target speed of around 30 kph) and using the throttle on the hand to maintain engine speed at an even 1,800rpm thus ensuring an even pressure of oil.

Once the speed is at a high point Once the tractor is running, the driver dips his clutch, and then pulls on the lever for the spool, which brings the entire machine to a halt. It’s noticeable slower than normal without the help by the tractor’s brakes.

In the footwell, with the form of whirrrs and bleeps, your BrakeSafe box calculates its calculations and finally produces a figure for braking efficiency . It then spews an image of a grocery receipt to demonstrate that it.

To determine a precise estimate of the trailer’s stopping power , a bit of math is required to consider consideration of load weight into consideration. If the trailer is not loaded to its maximum, it’s still possible to create a clear figure of the speed at which it could stop if it were.

Then a percentage for the efficiency of braking is calculated trailers equipped with anchors that are activated by oil must be over 25%, and air-braked trailers should be able to reach 45percent.

Visit TrailerTek when shopping for Alko brake cable.

Anchors that are uprated

Farmers Weekly trialled various ways to upgrade trailer brakes hydraulically and examined the impact they had on the efficiency of braking.

Apart from replacing whole axles by using larger brakes, the biggest change came from the increase in ram size.

When you change from the 20mm diameter ram to a 30mm diameter ram stopping power increased by over 100 percent. Switching from quarter-inch to half-inch hoses made the difference by another 30 percent.

This is why the Irish company Farm Machinery now regularly upgrades trailer brakes for its customers to larger rams, and also changes the hoses that connect the five-way manifold , to the rams.

To accomplish this, a the three-eighth inch hose has proven to be adequate to not only increase brake power but also improving the return oil flow after brakes are released.

Five ways to increase your stopping power

As the Bagma data suggests, the majority fail and require more than just a slight adjustments. Here’s how the team from Ireland’s boost stopped power.

1. Hubs off

Unbolts the bolts holding the hub cab, then remove the hub cab. Remove the hub’s main bolt so that you are able to take care to remove the wheel bearing.

With a little gentle pressure and the use of a trolley jack underneath the drum, it will be capable of sliding the drum out to expose the brake shoes as well as any accessories.

2. Shoes off

From this point on it’s mostly a matter of getting rid of and de-rusting all the moving parts as well as friction surfaces.

With a pry bar in place to help absorb tension of the spring, slowly pull away the pins around which the shafts of the actuators rotate around, and squeeze their clips that hold them to release the pins.

On the other side of the brake shoes raise the spring and attempt to tap the hinge pins.

Every component in the brake system must be examined for excessive wear.

If they don’t move then pull the shoes to the side and then take them off.

You can then use some pressure to persuade them into coming free.

3. Clean up

Equipped with elbow grease, and emery cloth do a circular motion around each drum in order to get rid of any rust and give it an attractive metallic finish. In the event of any sharp ridges, the drums need to be put in the trash bin.

Utilizing the shoes, rub the surface until it is clear friction material. Then, remove any glaze.

The pins should be given a jolt using the wire wheel. Then take care to clean any areas that are subject to movement around the shafts, cams and pins.

4. Refit

Reassemble everything in the same way it was before by applying ample copper grease to the cams and pins.

Once the pins for hinges are in position and the spring that holds the two shoes then slide those pivots pins into the slots of the cam. Be mindful to ensure that their retaining clips are in the correct position.

5. Retest

The trailer should be run for this BrakeSafe test. Most of the time, Ireland’s team have found that brakes usually be able to pass following a thorough clean-up. If it’s near the limit, the hydraulic brakes are usually given an upgrade.