How to Unstick a Brake Proportioning Valve

How to Unstick a Brake Proportioning Valve
How to Unstick a Brake Proportioning Valve

Are you finding how do you unstick a brake proportioning valve? If your ans. is yes then you are came the right place. In this article, you’ll learn how to unstick a brake proportioning valve. Before that, let us read and get to know a few things about brake proportioning valves.

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A brake proportioning valve is a metering tool that balances the force between the front and back brakes.

The valve halts the brake fluid’s force or pressure to the back drum brakes in every heavy braking and emergency stops. Otherwise, the rear brakes will lock up and slide, attaining a lot of force from the master cylinder. According to the stress it receives, a spool or stem slides back and forth inside the piston bore of the proportioning valve.

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Proportioning valves can get stuck at either rear of the valve physique, needing a strategy to free them up.

How to Unstick a Brake Proportioning Valve(Step by Step)

Step 1

Put the car in ‘park’ for automated transmission and ‘neutral’ for a standard transmission. Then apply the emergency brake and raise the hood. Unscrew or unsnap the master cylinder cap. Fill the master cylinder with brake fluid to the full limit line. Keep the lid off. Utilize a floor jack to raise the vehicle at the front end and position two jacks below the frame near each wheel. Raise the car’s back, and place two jack stands under the back frame near each wheel.

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Step 2

Depress the brake pedal and note down if you have a brake light on the dashboard. In case your brake system has not been worked on lately or withstood no brake leaks from the wheel cylinders, callipers or master cylinder, possibilities are the brake proportioning valve is stuck in one place, stumbling the brake dash light. But, if your brake system has endured a leak or has been fixed up recently, you will need to conduct an ordinary brake bleed.

Step 3

Make an assistant sit in the driver’s seat and place a drain pan under the car’s right back wheel. Place a flare nut wrench on the brake bleeder valve, with the small nut with the round opening and exiting the backing plate. Make your assistant pump the pedal three to four times and grip it. Relax the brake bleeder with the flare nut wrench and enable brake fluid to leave. If you notice air and bubbles, repeat the procedure until a clear stream of brake fluid leaves through the valve.

Step 4

Conduct the same brake fluid bleed on the rest of the wheels, proceeding next with the left-back wheel until all the air is discarded. Restore your master cylinder with brake fluid. Bleed the right front bleeder valve, and then finally bleed the left front bleeder valve. Inquire the associate if the dash light has gone out. If not, check the proportioning valve, which will probably be placed next to your master cylinder.

The valve looks like a tiny cast-iron chunk, and it has a master cylinder line sustaining it, with back and front brake lines connected to it.

Step 5

Pat the proportioning valve with a tack hammer a few times lightly. Sometimes this frees up a rusted bore and piston spool inside the valve. Wriggle the brake light warning switch cord on the tip of the proportioning valve, making sure it has a tight and clean connection. Track down the brake line on the valve that directs to the back brakes, as well as the two single lines that direct to the left and right front brake calipers.

Step 6

Position a flare nut wrench on the back cap nut to the back brake line. Appoint your assistant to grip the brake firmly as you unlock the cap nut with the twist. If the brake pedal does not move downcast, assign your assistant stomp on the brake pedal with moderate to severe force, and hold it down firmly. When you hear a click from the valve, and the assistant notifies you, the dash light has gone out, halt and shut down the valve. The internal spool device inside the proportioning valve has changed positions and centred.

Step 7

Ask your assistant to keep the brake pedal down while you position the flare nut wrench on one of the front brake line cap nuts on the proportioning valve in case the dash light has remained on. Relax the cap nut with the twist, and ask your assistant to push the brake pedal gently.

Wait for fluid to escape, and have your assistant notify you once the light goes out. If that does not happen, ask your assistant to use the stomping force, and wait to listen for the click. Now close the cap nut. Conduct the same process on the remaining front brake line, opening the tube, foot on the brake, and some abrupt stomps.

Step 8 

Finally, bleed the back brake line again at the proportioning valve like you did before, incase you are still having a brake dash light. Bleed the front brake lines on the proportioning valve in the similar manner. This paradox of pressure will ultimately break the spool open inside the proportioning valve, neutralizing the pressure between the front and back brakes. The dash light will go off.

Now it’s your tern to do the work properly. In this article we tried our best to discuss about-how to unstick a brake proportioning valve easily. I think this steps help you doing your work.