Brake advice on a 1996 chevy Silverado 4x4
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From: hls on 24 May 2010 12:31 Thanks so much for your reply. I know you are supposed to replace both "shoes" but I ran out of time. I hope this is ok to just delay a week. SHoudl I also have the drums resurfaced? On the one side I replaced the shoes and all the springs. Plan to do the same to the other side. ******It can be really dangerous to "repair" one side only and drive with it. You are taking your life in your hands when you do this. You can look at the condition of the drum surface and decide whether it needs to be resurfaced. If it is heavily grooved, then it much be turned or replaced. For minor scratches, you may get by without it, but DONT resurface one and not the other. ******** Could this cylinder be ok? ********* Yes, it could be okay...or not. I assume you bled the brakes and went through the preliminary adjustment of the shoes? ********* FWIW by the way my emergency brake is not working very good. (It started several weeks before I even attempted to replace shoes.) ********* When you finish the other side, and have bled and preadjusted the shoes, then you can work on the parking brake. There should be a place where the cable from the parking brake pedal or lever can be adjusted. ******* Do I pump the brakes with engine on or off? ******* Pump up the brakes with the engine running so that the vacuum assist will work. Hold them in hard and see if the (usually after a short pause) pedal seems to release and move toward the floorboard. If it does, you can be almost 100% sure the master cylinder (under the hood) is faulty.
From: jim on 24 May 2010 13:33 stryped wrote: > > Thanks so much for your reply. > > I know you are supposed to replace both "shoes" but I ran out of time. > I hope this is ok to just delay a week. SHoudl I also have the drums > resurfaced? On the one side I replaced the shoes and all the springs. > Plan to do the same to the other side. Doesn't sound like you need the drums resurfaced. It sounds like your old shoes needed replacing because they got old rather than worn. > > I did not replace any wheel cylinders. I had to force the shoes on > because of the spring tension. Where the shoe contacts the rubber boot > I saw oil dripping down. I have checked under the vehcile after > drivign and parkign overnight and see nothing ont he ground. Could > this cylinder be ok? I really dont want to replace it. My manual says > the shoes have to come back off and I had a heck of a time getting > them on there. They make a pliers like tool for installing and removing the springs that makes the job pretty easy. I don't think they cost that much. > > FWIW by the way my emergency brake is not working very good. (It > started several weeks before I even attempted to replace shoes.) > > Do I pump the brakes with engine on or off? Try it both ways. When the engine is off the pedal should feel like it is higher and harder than when the engine is running. Pumping the brakes shouldn't make any difference (after you depleted the booster vacuum) unless there is air in the lines or the rear brakes are not adjusted correctly. I think the point was does pumping the brakes and holding get rid of the spongy brake feeling? Does the pedal hold steady or does it sink slowly when you hold the pressure? -jim
From: stryped on 24 May 2010 14:04 On May 24, 11:31 am, "hls" <h...(a)nospam.nix> wrote: > Thanks so much for your reply. > > I know you are supposed to replace both "shoes" but I ran out of time. > I hope this is ok to just delay a week. SHoudl I also have the drums > resurfaced? On the one side I replaced the shoes and all the springs. > Plan to do the same to the other side. > > ******It can be really dangerous to "repair" one side only and > drive with it. You are taking your life in your hands when you do this. > > You can look at the condition of the drum surface and decide whether it > needs to be resurfaced. If it is heavily grooved, then it much be turned > or replaced. For minor scratches, you may get by without it, but DONT > resurface one and not the other. > ******** > Could this cylinder be ok? > ********* > Yes, it could be okay...or not. I assume you bled the brakes and went > through the preliminary adjustment of the shoes? > > ********* > FWIW by the way my emergency brake is not working very good. (It > started several weeks before I even attempted to replace shoes.) > > ********* > When you finish the other side, and have bled and preadjusted the shoes, > then you can work on the parking brake. There should be a place where > the cable from the parking brake pedal or lever can be adjusted. > > ******* > > Do I pump the brakes with engine on or off? > > ******* > Pump up the brakes with the engine running so that the vacuum assist > will work. Hold them in hard and see if the (usually after a short pause) > pedal seems to release and move toward the floorboard. If it does, you > can be almost 100% sure the master cylinder (under the hood) is faulty. Is it possible for the cylinder to leak like it did only temporarily?? No I did not bleed the brakes, I never took anythign off other than the shoes. My manual did not say anything about it. SHould I have? I drove in reverse and applied the brake several times to adjust them. Was that right?
From: aarcuda69062 on 24 May 2010 14:51 In article <07300393-2e0b-4ce2-8534-83f78d249a9b(a)y12g2000vbg.googlegroups.com>, stryped <stryped1(a)yahoo.com> wrote: > Is it possible for the cylinder to leak like it did only temporarily?? In your dreams... > No I did not bleed the brakes, I never took anythign off other than > the shoes. My manual did not say anything about it. SHould I have? It is not mandatory to bleed the wheel cylinders, nor is it necessary when one is merely replacing brake shoes unless there is another problem that requires attention. > I drove in reverse and applied the brake several times to adjust them. > Was that right? Dunno... did you inspect, clean and lube the adjuster mechanisms when you had everything apart? 'cuz it's entirely possible after 300K miles that the adjusters are seized solid and all the backing and braking in the world won't do a damn thing.
From: hls on 24 May 2010 14:55
"stryped" <stryped1(a)yahoo.com> wrote in message news:07300393-2e0b- Is it possible for the cylinder to leak like it did only temporarily?? No I did not bleed the brakes, I never took anythign off other than the shoes. My manual did not say anything about it. SHould I have? ****** The wheel cylinders can leak when you are trying to get the shoes held down, get the actuating rods back between the shoes and the pistons in the cylinder, etc. This is because the pistons inside the cylinders can be pressed too far to one end or the other of the cylinder bore, and some fluid could leak out. This, in itself, is not a serious problem if you get them back like they should be AND if they are not corroded and leaking. If you could have a person who knows how to reassemble the rear drum brakes help you do this just once, you would find it a lot easier next time. ******* I drove in reverse and applied the brake several times to adjust them. Was that right? ****** Normally, you pre-adjust the rear brakes before you go through that step. If the brakes are too far out of adjustment, the autoadjusters will not activate properly on backing up and you will have a problem. To do this, you put the drum back on. Then, there is usually a hole in the backing plate of the rear brake assembly through which you can insert a tool and advance the starwheel until almost all the slack is taken out of the braking system...The tool required looks a little like a flatblade screwdriver, and a fine blade screwdriver has been used millions of times to do this job. Jim refers to tools required to do this job.. I have never found a use for the special brake pliars that are often advertised and are found in FLAPS. There is a special tool used to put the retainers on the hold down rods that is helpful, but this job can be done with a regular set of pliars, with a little practice.. There is also a special tool that can be used to remove and replace the springs and, to me, this one IS helpful, but you can do the job, if you are strong, with a set of diagonal cutters...They allow you to get a good grip on the springs and - despite what it sounds like - they do not damage the springs. If a car is getting old, I would at least inspect the wheel cylinders. I would guess that not too many people rebuild them nowadays because they are normally fairly cheap to replace. BUT if you want to replace them, be careful and do not booger up the brakeline nut that screws into the old ones when you try to replace them...Use a "line wrench" - not a Crescent nor even an open end wrench. One last thing...did you take the adjusters apart, clean them in solvent, and re-lubricate them before you put them back on? You want to be sure those adjusters move freely. Nota Bene: The adjusters on the left side are different from those on the right and they are not at all interchangeable. You dont have to worry about this since you did only one side, and there should have been no chance you would get the wrong one on the wrong side. |