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I really thought you you bit off more than you could chew when you escalated the project to the turbo. But you proved it to all of us that you can dream big and if you stay with it success can be achieved. A very well deserved congratulations!
I’ve attached a schematic of your dad’s rear anti-lock brake system. The anti-lock mechanism as shown in [attachment=9167]Rear Anti-Lock Schematic (manufactured by Kelsey-Hayes…now TRW) only includes the Isolation/Dump Valve and an Accumulator (not shown) to store the released fluid. The metering valve, brake light switch valve, and proportioning valve are still contained int he Combination Valve. The problem seems to stem from the brake light switch valve moving from the pressure imbalance during bleeding and thus not permitting full flow to the brake caliper being bled. Two methods I have seen work. One is to hold the rubber button in while bleeding as recommended by the factory or alternatively purchase a special pin that takes the place of the safety switch while bleeding that keeps the valve from shifting. (Ref: https://www.performanceonline.com/Combination-Proportioning-Valve-Bleed-Tool/ )
Good luck with the bleed. This has been a problem for many other vehicles using this combination valve.
Hi Eric,
(Please excuse this reply if you have already seen it as I may have placed it in the wrong category.)Your Dad’s truck has a combination brake valve (a proportioning valve,a rear wheel pressure hold-off metering valve, and a failure mode pressure switch). You did not mention it during the bleeding process at the rear wheels, but the little rubber button on the end of the unit (metering valve) must be held in using a makeshift tool or by having an assistant hold it in. Otherwise, it is my understanding that the rear brakes will not bleed properly. Hope this helps.
Great step-by-step “how-to” video.
Thanks for this very useful video. My son’s 2004 Odyssey with 216,000 well-worn miles had the door jamb shut completely and broke the cable for the same reason you suggested that doors could stick when the rollers went bad. In fact, his rollers had completely disintegrated. I was pressed for time, so I replaced the rollers, but did not bother with fixing the broken cable, but left the door as manually operating. It works great for now. When the weather warms up again, I’ll look into getting the cable repaired.
Thanks again for showing all your great tips.
Dave R. Beavercreek, OH
Eric,
You are well worth the wait. You have helped so many people and I personally have learned a lot from all of your videos. I know you will be back as good as ever. Take whatever time you need to find that clean plate again.
Dave R.
Great video Eric. Just like old times! If you mix one or two of these a month with your Fairmont videos (which I’m also really getting into now) I think this will be a happy balance for your viewers. I like how you figured out how to get the rack out from the side as that makes it easier for the guy at home on his garage floor to accomplish. Keep up the good work.
Problem solved! The rollers had completely worn away which caused the door to jam and the cable to break. By making sure the door latch was in the open position and by tugging on the piece of cable left on the roller from the outside, the door finally sprung open. The repair after that was easy. Install a new set of rollers purchased from the local Honda Dealer, trim off the remaining cable and convert it to a manual door. Works great and can be converted later back to automatic with the purchase of a cable kit or a new (or used) door motor that comes with the cables.
I agree to get the caliper fixed first to eliminate that problem. Also, if you are bleeding manually with the master cylinder, make sure you are using the correct technique. Have a buddy push the pedal for you: 1) Open bleeder valve; 2) Push pedal down and hold; 3) Close bleeder valve; 4) Release pedal. Repeat until all the air bubbles are gone from the line. (A clear hose on the bleed nipple works best to see the air bubbles come out.) That way the master cylinder acts like a pump to positively push the fluid out. Good luck.
Most brake pulsation is caused by warped or rusted rotors. They can be replaced or taken to a machine shop to see if they can be resurfaced. See Eric’s video on his brake rotor/drum lathe. So you might try that next. A leak would probably just cause them to be less effective but not necessarily cause pulsation.
I do not know of any vacuum specs required for bleeding brakes. With the ABS system properly re-homed, fluid flows easily through the system. If air is trapped in the lines all you are trying to do is flow the fluid out of the wheel cylinder and the air will come with it. Have you tried to manually bleed the brakes with the master cylinder. If done correctly, this works very well. See my response earlier that tells how to do it. (open caliper bleeder valve, push brake pedal down and hold, close valve, release pedal…. repeat until fluid runs clear). You can also do this with the bleeder valves on the ABS unit, but these should bleed very easily.
One other question. Did you get the rear brakes put back properly with all the springs hooked up correctly after you changed the wheel cylinder? This can also cause spongy brake pedal (excess travel).
Glad to hear you got the car running again. If the ABS is re-homed properly for the rear brakes, it should be easy to bleed with a vacuum or pressure bleed system or using the master cylinder. The fronts have bypass solenoids so they can bleed even if the system is not re-homed. Remember when using the master cylinder method, it is much easier with two people: one pushes the brake pedal and the other opens and closes the bleeder valve at the caliper. 1) Open valve; 2) Push brake pedal to floor and hold it there; 3) Close bleeder valve; 4) Raise pedal. Repeat until air is gone from the fluid. Good luck.
I’ve attached a schematic of the rear ABS system. If the unit is working, each time you turn on the key, the unit will re-home the rear ABS pistons. This will open the valves that permit fluid flow from the master cylinder to the rear wheels. If the unit is no functioning properly and the pistons do not re-home then you can turn your key on and off to see if that re-homes the piston. You can go to a shop with at GM Tech-2 diagnostic tool and they can try to re-home the pistons for you, or you may simply need a new unit. If your ABS trouble light is on and you would then be driving with ordinary brakes (no ABS active), you could try the following for a short-term fix. Remove the unit. Take off the lower cover. Remove the center nut and gear. Turn the screw counter-clockwise to re-home the pistons. Replace the gear and nut and cover. This is not recommended long term (no ABS), but it will re-home the unit until it is replaced.
Good luck getting your brakes working again.Hi Eric,
I ran across this video after seeing the difficulty you had with the Fairmont springs.
It looks like there is an inexpensive tool that fits on the lower A-arm to keep the spring in place.
Hope this helps.
Keep up the great work. I’m looking forward to when your Fixing It Forward videos start again.
Dave R
Dayton, OHI think you can only re-home the ABS unit electronically. The unit uses a motor, gear, and ball screw arrangement to move a piston up and down inside a bore. When the piston is at the top, it opens a valve to permit fluid to flow to the rear brakes. Did the ABS unit work before you took off the wheel cylinder? Did you have a yellow ABS light staying on when you drove the car? That could also explain why the unit did not re-home properly. I’ll try to find out some more information on the unit.
I am an ex-Delphi Chassis engineer and worked on your ABS brake system. As long as the ABS system was working, the pistons inside the unit will automatically re-home and open up valves to permit fluid to flow to the rear brakes in non-ABS mode. So most likely, if your ABS was working then this should not be a problem.
1) Are you using the proper manual bleed procedure? (i.e. open the bleeder valve, push the pedal to the floor and hold it there, close the bleeder valve, release the brake pedal, repeat the process), This acts like a pump to move fluid into the brake lines.
2) Did you let the fluid reservoir get empty? Number one rule… never let the reservoir get low on fluid as that allow air into the master cylinder. If so, you may have to re-bleed the master cylinder. Loosen the rear brake pipes at the ABS modulator under the hood of the car. See if fluid comes out there. That will confirm the master cylinder needs bleeding or you do have a defective ABS unit (yellow ABS light should glow on dash) and the unit has not re-homed properly. Leave the brake pipes loose there and then slowly pump the brake pedal a number of times to see if you can get the air out of the system.
3) If you have a pressure bleeder and no fluid is coming out at the modulator, that is a sign it is not re-homing.
4) If all else fails, a GM dealer or a good shop will have a “Tech-2” service tool that can diagnose the unit and automatically re-home it as well as pressure bleed the rear brakes. Good luck.