i replaced the hydro booster pump on a 99 chevy old body style w/ a 454 today, break pedal goes straight to the floor & breaks lock up as soon as i crank it, i've tried unhooking the lines to the reservoir, open all valves on each wheel, nothing. anyone have an answer for this one??
Country: United StatesMake: ChevroletModel: 2500Year: 1999Engine: 454
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HI I am Daniel Are you talking about the abs Hydraulic module. and has any work been done to brake booster or master cylinder. ?
not the abs module, we replaced the booster pump that's behind the brake fluid reservoir, the entire booster, even the part that bolts through the fire wall. as soon as we cranked it up, brake pedal goes straigth to the floor forcefully and locks up the brakes
Did it do this before? what was symptoms you change it for?
it was leaking fluid out of the front 2 small seals that look like freeze plugs, not really sure what their function is but they were leaking power steering fluid like crazy
Have you bleed the system good?
I will get you bleeding procedures.
dont accept just reply for now.
yeah we tried normal bleeding, you know, pump brakes, open one valve at a time, etc. but apparently w/ a closed system on a booster pump like this, the bleeding procedure is TOTALLY different
Power Steering System Bleeding
Important Power steering fluid level must be maintained throughout bleed procedure.
Important With hydro-boost only, the oil level will appear falsely high if the hydro-boost accumulator is not fully charged. Do not apply the brake pedal with the engine OFF. This will discharge the hydro-boost accumulator.
Vehicles equipped with hydro-boost systems or longer length power steering hoses may require turns up to 15 to 20 stop to stops.
Let me know if you still have trouble even after accept.
and if that dont work you will have to do full blown bleed and get tools at auto parts store loaner program.
Tools Required J 35555 Mity Vac J 43485 Power Steering Bleeder Adapter
Important: Use clean, new power steering fluid type only.
If the power steering system has been serviced, an accurate fluid level reading cannot be obtained unless air is bled from the steering system. The air in the fluid may cause pump cavitation noise and may cause pump damage over a period of time. When adding fluid or making a complete fluid change, always use the proper power steering fluid. Failure to use the proper fluid will cause hose and seal damage and fluid leaks.Important: Hoses touching the frame, body, or engine may cause system noise.
Verify that the hoses do not touch any other part of the vehicle.Important: Loose connections may not leak, but could allow air into the steering system.
Verify that all hose connections are tight.Important: Maintain the fluid level throughout the bleed procedure.
Remove the pump reservoir cap. Fill the pump reservoir with fluid to the "FULL COLD" level.
Attach J 43485 to J 35555 or equivalent. Place J 43485 on or in the pump reservoir filler neck. Apply a vacuum of 68 kPa (20 in-Hg) maximum. Wait 5 minutes. Typical vacuum drop is 7-10 kPa (2-3 in-Hg). If the vacuum does not remain steady, refer to Excessive Vacuum Drop Diagnosis at the end of this procedure.
Remove the J 43485 and the J 35555. Reinstall the pump reservoir cap. Start the engine. Allow the engine to idle. Turn off the engine. Verify the fluid level. Repeat steps 9 through 11 until fluid stabilizes.
Start the engine. Allow the engine to idle.Important: Do not turn steering wheel to lock.
Turn the steering wheel 180-360 degrees in both directions 5 times.
Switch the ignition off. Verify the fluid level.
Remove the pump reservoir cap.
Attach J 43485 to J 35555 or equivalent. Place J 43485 on or in the pump reservoir filler neck. Apply a vacuum of 68 kPa (20 in-Hg) maximum. Wait 5 minutes. Remove the J 43485 and the J 35555. Verify the fluid level.
Reinstall the pump reservoir cap.EXCESSIVE VACUUM DROP DIAGNOSIS
Tools Required J 35555 Mity Vac J 43485 Power Steering Bleed Adapter
If the vacuum continues to drop, remove the pressure and return hose from the pump. Install the plugs (1) (2) supplied with J 43485 into the pressure and return port.
Attach J 43485 to J 35555 or equivalent. Place J 43485 on or in the pump reservoir filler neck. Apply a vacuum of 68 kPa (20 in-Hg) maximum. If the vacuum drops again, repair or replace the pump. If the vacuum holds steady, continue to check the other parts of the steering system.
Be aware of periodic bubbles that indicate a loose connection or leaking O-ring seal in the return hose or the pressure hose.Important: Fluid must be free from bubbles and foam.
Fluid must be free from discoloration.Observe the fluid. If condition persists, replace the following parts:The return hose clamps The return hose O-rings The pressure hose O-rings The gear cylinder line O-rings The reservoir to pump O-ringRepeat the bleed procedure from the beginning. Drive the vehicle approximately 16 kilometers (10 miles) to warm the system to operating temperature. Evaluate vehicle on a smooth flat surface. Verify the following conditions:There is smooth power assist. The vehicle operates quietly. The pump maintains the proper fluid level. There is no leaking in the steering system. The fluid is free of foam or discoloration.
If this doesnt work the master cylinder is bad.
Let me know if you need any help along the way.
Most of our fleet is chevy.
oh freakin hell, hahhaaha, alright, i'll try all of this in the a.m.
so this is the procedure for the brake pedal issues and brake bleeding? i know they both run off the same pump but it seems more for power steering issues instead of the locked up brakes and pedal being pulled to the floor
Yes this is all power steering and fluid. You made sure it has power steering fluidright? The master cylinder has brake fluid. But it gives you that smooth power to stop easy. It wont be bad as soon as you read all of it and see most of it is blah blah. But its not hard although you may need those tools if the first doesnt work. I think you will be fine. I work on these systems all the time.
Hi, I want to follow up with you to make sure you have not missed any questions you wanted to ask. There is no additional accept needed. Just let me know if tyhere is anything further I can help with. Thanks Daniel