Troubleshooting brakes
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==Brake pedal goes to the floor== | ==Brake pedal goes to the floor== | ||
You will need a helper for this. | You will need a helper for this. | ||
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Assuming the fluid level in the master is still good, take a pair of pinch–off pliers and pinch off the Flex hose that joins the rear breaks to the frame. Pump up the brakes. Is the pedal now firm and not leaking down? If yes, then the problem is in the rear. Remove the wheels and inspect the rear drums, shoes and wheel cylinders, or inspect the Rear Rotors, pads and calipers. Repair, remove and replace the items needed to restore the system to OEM specs and serviceability. If pinching off this hose made no change, then leave the hose pinched off and then continue to diagnose the system. Follow the lines along the frame back up to the master and try to notice any signs of obvious leakage. | Assuming the fluid level in the master is still good, take a pair of pinch–off pliers and pinch off the Flex hose that joins the rear breaks to the frame. Pump up the brakes. Is the pedal now firm and not leaking down? If yes, then the problem is in the rear. Remove the wheels and inspect the rear drums, shoes and wheel cylinders, or inspect the Rear Rotors, pads and calipers. Repair, remove and replace the items needed to restore the system to OEM specs and serviceability. If pinching off this hose made no change, then leave the hose pinched off and then continue to diagnose the system. Follow the lines along the frame back up to the master and try to notice any signs of obvious leakage. | ||
| − | Find the flex hose on the | + | Find the flex hose on the left side caliper and use another set of pinch off pliers to pinch off the flex hose between the line and the caliper. Check the level of the fluid and pump up the brakes. Is the pedal now firm and not leaking down? If yes, then the problem is in this caliper. If the wheel is still on, remove the wheel and inspect this caliper and surrounding structure. Repair, remove and replace the items needed to restore the system to OEM specs and serviceability. If one caliper is bad expect to do both as the brakes should always be done as a set. |
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| + | Find the flex hose on the right side caliper and use another set of pinch off pliers to pinch off the flex hose between the line and the caliper. Pump up the brakes. Is the pedal now firm and not leaking down? If yes, then the problem is in this caliper. If the wheel is still on, remove the wheel and inspect this caliper and surrounding structure. Repair, remove and replace the items needed to restore the system to OEM specs and serviceability. As noted before; if one caliper is bad expect to do both as the brakes should always be done as a set. Likewise always fail safe (go/no-go) check your rotors with a micrometer and re-true them. Rotors also should always be replaced in pairs. | ||
If after all this and the pedal still will not pump up or hold a pedal, re-inspect all the lines from the master to the flex hoses, use a flash light if needed to inspect the lines running along the frame and again look for leaks and signs of leakage. | If after all this and the pedal still will not pump up or hold a pedal, re-inspect all the lines from the master to the flex hoses, use a flash light if needed to inspect the lines running along the frame and again look for leaks and signs of leakage. | ||
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You should now know where the leak is and how to correctly price out the repair for your customer. | You should now know where the leak is and how to correctly price out the repair for your customer. | ||
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| + | Destructive testing method is even faster, but by its nature if there is a problem…, you will be fixing something!!! | ||
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| + | Set the car on the lift and get it ready but don’t lift it. Open the hood check the fluid level in the master, top it off and securely replace the cover. | ||
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| + | Check the obvious first and verify that the brake pedal is connected properly to the actuator rod and not broken or bent. | ||
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| + | Get in the car, engine off, radio off and simulate a panic stop. | ||
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| + | Pump the brakes full travel 3 – 5 times hard. If there is a weakness in the system, it WILL break!!! | ||
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| + | Listen for pop and hiss from the brake lines and wheels. Get out of the car, check the fluid level and replace the top, and lift the car. | ||
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| + | With a flashlight, trace and inspect all your lines, the backs of all of the tires and look for signs of leaks. If there is no leaking, and you had no pedal at all, then the master is trash. You will need to R & R the master. | ||
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| + | Inspect the front and rear brakes and price out what you have to do to bring car back to OEM specs. If all the pads and shoes are good, then at a minimum figure on inspection (Micrometer) and re-truing (turning) the drums and rotors and button up. | ||
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| + | Remember…, air is compressible and liquid is not. | ||
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| + | If the pedal is spongy it has air in the system. | ||
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| + | If there is no pedal or will not firm up or hold a pedal, you are lacking fluid. | ||
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| + | Loss of fluid usually means a leak. | ||
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[[Category:Brakes]] | [[Category:Brakes]] | ||
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[[Category:Troubleshooting]] | [[Category:Troubleshooting]] | ||
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