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Read the WELCOME ALL BMWFANATICS post.
Changing brake pads
- Thread starter JENICH
- Start date
Hi. Yes please explain as I changed pads and I opened the res cap. Never open the bleeder nipple. I'm worried now. Car brakes seem fine. Although and maybe ralf can answer this. When I press brakes its as if sometimes the piston is not right out I hear a small tuck sound. Or tick sound. Not sure if that is nothing.
Also guys a friend of mine said I must never just push the piston back he showed me a tool used that turns the piston backwards and it goes in. But isn't that on models with a piston that design to do that. I'm sure ours are not the thread pistion isn't. Pushing it back is safe.
Although I did the brakes myself and its fine I wanna take it to a brake place to check it.
See how nice is it to learn stuff on here. :joy:
Oh and about the allen key snapping. I bought a spline socket set. Its much thicker and safer then the allen key set and easy to open. Also use some copper paste on the bolts when putting back so next time its easier to open.
I don't trust the allen keys they too weak. :thumbdo:
Lastly if any fanatic needs help changing pads. You can visit me. Will be glad to help. Its extremely easy to change. The hardest part is to jack the car up and down. Lol. :biglol:
Also guys a friend of mine said I must never just push the piston back he showed me a tool used that turns the piston backwards and it goes in. But isn't that on models with a piston that design to do that. I'm sure ours are not the thread pistion isn't. Pushing it back is safe.
Although I did the brakes myself and its fine I wanna take it to a brake place to check it.
See how nice is it to learn stuff on here. :joy:
Oh and about the allen key snapping. I bought a spline socket set. Its much thicker and safer then the allen key set and easy to open. Also use some copper paste on the bolts when putting back so next time its easier to open.
I don't trust the allen keys they too weak. :thumbdo:
Lastly if any fanatic needs help changing pads. You can visit me. Will be glad to help. Its extremely easy to change. The hardest part is to jack the car up and down. Lol. :biglol:
Ralf*
///Member
CliftonH said:
sorry, cannot answer this either, I come from an "old-school" engineering background...late 70's early 80's...ABS didn't even exist back then (I think) although it did exist on aircraft (my apprenticeship and tradesman) but a totally different logic and system.
so any and all new info posted will add to my old-man learning experience as well
Charlie Brown
Member
My recomendation is per my Haynes manual. I have a terrible habit of reading manuals or instructions after I have done the job itself. I only noted this after doing a pad change and don't think I did any real damage to my old cars system. However it is in the manual !
Some cars do the a "threaded" piston I believe, later model golfs I think.
Logically thinking it does make sense not to force the old contaminated fluid through your braking system. Try release the nipple so the path of least resistance is through the nipple and not back to the resevoir.
Some cars do the a "threaded" piston I believe, later model golfs I think.
Logically thinking it does make sense not to force the old contaminated fluid through your braking system. Try release the nipple so the path of least resistance is through the nipple and not back to the resevoir.
Hi Charlie, i have changed brake pads on 100's of cars ranging from the 70's all up till today's technology. It is not necessary at all to open up the nipple, as no damage will be caused. Do remember the the sole purpose of the abs is to actually reduce the amount of brake fluid running into the caliper to prevent wheel lock up. In order to achieve this, the abs pump actually sucks fluid from the system to reduce the braking pressure, this is why you will experience the brake pedal pulsation in extreme braking circumstances. Hence, when pushing the caliper piston in, the fluid will run straight to the brake master cylinder and not into the abs system.
When replacing your brake pads, it would be much easier to use a g clamp to push the piston in before your remove the caliper bolts, once thats done, remove the anti rattle clip with a screwdriver using much care as these can spring out and hit you in the eye, remove the caliper and replace the brake pads. Take note that the caliper bolts play a dual role and also serve as slide pins to allow free movement of the caliper. Remove these completely from the caliper, use some Q20 to clean them and their seating sleeves, wipe them clean and dry and thereafter apply some high temperature/wheel bearing grease to ensure freedom of movement. replace the assembly and the wheel, then pump the brake pedal a few times to return the fluid into the caliper. Repeat this on the other side. Any brake fluid overleak is a result of over filling, it is not necessary to remove the cap you can simply puor some water over the reservoir to dilute and wash away excess brake fluid that may have leaked.
The threaded\screw type system is used in vehicles where the rear brake pads are used to lock the rear wheels once the handbrake is pulled. (best to let a professional chage these brakes, it can be a source of great pain) It is very common in most Euro models, although i have not personally seen this system used on BMW applications.
Contaminants will flow throughout the brake fluid system due to brake fluid degradation over time, it is best to replace the brake fluid at annual intervals with a dot 4 or higher grade brake fluid.
:thumbs:
When replacing your brake pads, it would be much easier to use a g clamp to push the piston in before your remove the caliper bolts, once thats done, remove the anti rattle clip with a screwdriver using much care as these can spring out and hit you in the eye, remove the caliper and replace the brake pads. Take note that the caliper bolts play a dual role and also serve as slide pins to allow free movement of the caliper. Remove these completely from the caliper, use some Q20 to clean them and their seating sleeves, wipe them clean and dry and thereafter apply some high temperature/wheel bearing grease to ensure freedom of movement. replace the assembly and the wheel, then pump the brake pedal a few times to return the fluid into the caliper. Repeat this on the other side. Any brake fluid overleak is a result of over filling, it is not necessary to remove the cap you can simply puor some water over the reservoir to dilute and wash away excess brake fluid that may have leaked.
The threaded\screw type system is used in vehicles where the rear brake pads are used to lock the rear wheels once the handbrake is pulled. (best to let a professional chage these brakes, it can be a source of great pain) It is very common in most Euro models, although i have not personally seen this system used on BMW applications.
Contaminants will flow throughout the brake fluid system due to brake fluid degradation over time, it is best to replace the brake fluid at annual intervals with a dot 4 or higher grade brake fluid.
:thumbs:
Charlie Brown
Member
Thanks Avi
Couldn't agree more that the G-Clamp method is the easiest, in fact I have used it myself once or twice. I generally used a wooden handled hammer and pushed the piston back (with the woden part) - however that doesn't mean that it's the correct way.
With due respect Q20 is not a brake cleaner, allowing water the reservoir to overflow and just rinsing off with water is easliy avoidable with a little care and attention. Copperslip / paste is better for the guide pins.
As i stated, I too for the past 20 years simply pushed the piston back, until I read my Haynes manual (that I have had for 8 years mind you) and realised that it's not ideal.
Having done it the "correct" way last time round it really wasn't a big deal, particularly if you are working on a car with old brake fluid that you don't want contaminating your braking system.
Use it / don't use it just a little info that I thought I'd share with the fanatics.
Couldn't agree more that the G-Clamp method is the easiest, in fact I have used it myself once or twice. I generally used a wooden handled hammer and pushed the piston back (with the woden part) - however that doesn't mean that it's the correct way.
With due respect Q20 is not a brake cleaner, allowing water the reservoir to overflow and just rinsing off with water is easliy avoidable with a little care and attention. Copperslip / paste is better for the guide pins.
As i stated, I too for the past 20 years simply pushed the piston back, until I read my Haynes manual (that I have had for 8 years mind you) and realised that it's not ideal.
Having done it the "correct" way last time round it really wasn't a big deal, particularly if you are working on a car with old brake fluid that you don't want contaminating your braking system.
Use it / don't use it just a little info that I thought I'd share with the fanatics.
Charlie Brown said:
Just to clarify a few points charlie.
(a) using q20 to clean up the guide pins was a recommendation to the guys who dont really want to spend R80 or so on a can of brake cleaner and who more than likely would have a can of q20 at their disposal. It is , as we know, a very effective cleaning and anti corrosive agent.
(b) copper slip/paste does harden over time, especially when exposed to high temperatures, this will cause guide pins to seize up as i have found on many occasions. Using a silicone based, high temperature grease that will not swell the bushes is the best way to go.
(c) brake fluid is hygroscopic and will corrode the brake system if not changed regularly, this will occur throughout the braking system from caliper to reservoir. you will notice that even the fluid in the reservoir becomes discoloured showing signs of degradation. It was my recommendation that the fluid be changed at least once a year with a high grade brake fluid that would not be prone to contamination thereby ensuring the entire system remains clean and free of contaminants.
I am glad we can share opinions on the forum, and i have a huge amount of respect for the Haynes manuals, because they do help the layman understand cars better, but please also remember, they are not, and neither is anyone else, the be all - end all of motor vehicle maintenance.
:thumbs:
Hugo_za said:
the brake fluid system is a sealed system, any bubbles formed would be as a result of a failure within the brake master cylinder or possibly the reservoir running dry at some point allowing air into the system or it could be that there was a bleed done, but not correctly.
one would only bleed the brake system as a means of changing brake fluid or after a repair to a brake component (pipe changed, seals replaced or overhauling of calipers/cylinders)
