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Compressing the caliper piston in that manner forces old fluid and dirt back up into the Master cylinder / reservoir.

Failing to "rough up" the rotor surface will inhibit new pads seating properly.
 

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Compressing the caliper piston in that manner forces old fluid and dirt back up into the Master cylinder / reservoir.
What is the correct way to compress the caliper piston?
 

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Thank's for posting

I think buddy was referring to draw filing or stoning the outer rust ring on the caliper fush to the rest of the caliper.

There is probably a small step in the caliper above the pad contact area.

This would help avoid wearing a groove into the new pads.

I like the music in the video, who's the band and the name of the tune.

Regard's
 

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What is the correct way to compress the caliper piston?
If you are a perfectionist like me, first suck all the old fluid out of the Master Cyl reservoir and replace with fresh Brake fluid. Then crack open the slave tap/drain with plastic hose attached to the opening /so it will drain into a container when you open the tap. Then you slowly compress the piston back into the caliper and observe the old fluid flowing into the container. Seal off the tap when piston is fully compressed. You'll need to bleed the brakes when done with the whole job. The idea is to get as much fresh fluid into the system as possible and not contaminate with old.....

For the hyper-perfectionist - open the drain at the slave and just let gravity pull out the old fluid, until it runs clear - keep in mind the BF reservoir must not be allowed to empty out of fresh new fluid. It's a challenge to keep an eye on two places ;-) This method takes too long for anyone on the clock, but the payoff is that there's little or no chance any old fluid will be forced back up into the system. Again, bleed the system when done - all around - starting with the wheel furthest from the Master Cylinder working your way 'round to the closest wheel to the MC..
 

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I just use some 80 grit sand paper on the surfaces to rough it up a bit, using an irregular pattern to grind off the glaze....
 

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If you are a perfectionist like me, first suck all the old fluid out of the Master Cyl reservoir and replace with fresh Brake fluid. Then crack open the slave tap/drain with plastic hose attached to the opening /so it will drain into a container when you open the tap. Then you slowly compress the piston back into the caliper and observe the old fluid flowing into the container. Seal off the tap when piston is fully compressed. You'll need to bleed the brakes when done with the whole job. The idea is to get as much fresh fluid into the system as possible and not contaminate with old.....

For the hyper-perfectionist - open the drain at the slave and just let gravity pull out the old fluid, until it runs clear - keep in mind the BF reservoir must not be allowed to empty out of fresh new fluid. It's a challenge to keep an eye on two places ;-) This method takes too long for anyone on the clock, but the payoff is that there's little or no chance any old fluid will be forced back up into the system. Again, bleed the system when done - all around - starting with the wheel furthest from the Master Cylinder working your way 'round to the closest wheel to the MC..
Wow - I've never done that. Is this considered standard practice? Do you suck the old fluid out of the master cylinder each time you change pads or rotors?
 

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Wow - I've never done that. Is this considered standard practice? Do you suck the old fluid out of the master cylinder each time you change pads or rotors?
Because DOT 3 brakefluid is hygroscopic (wicks up moisture), I try to at least refresh the Master Cylinder's reservoir fluid once every 24 months - assuming I haven't R&R'd pads or rotors [in that time frame] - which is when I do a full flush on everything. Moisture is the enemy of the braking system. The newer syn brake fluids don't seem to have this problem, IIRC. Guess I need to do a bit more research on them, as it's really a PITA to have to think and remember to refresh old DOT 3 fluid....

Most folks don't keep their cars forever.....like I do. So this kind of TLC is considered over the top for many [who simply consider their cars to be like Kleenex - use once and throw away].
 

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I keep my cars forever too. My Tercel is 18 years old this year and the Camry 13 years old. I have to admit though, that I have never flushed the brake fluid on either of them. I didn't realize DOT 3 is hygroscopic. What happens if moisture gets inside the brake system? The brake system is sealed, so theoretically no moisture should get inside - yes?
 

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The thinking is that the because the DOT 3 stuff will hold moisture, not flushing it will allow brake components to corrode. I suppose this is true but I've never had to replace any brake components because of a corrosion problem on car that is being driven regularly. And I never flush the brake system. All you need is an incompressible fluid in there for the system to work, dirty or not. You might get an extra 10-20K miles out of the hydraulic components but I doubt it. Brake parts generally fail because of mechanical wear. I typically get well in excess of 100K miles out of the hydraulic components in the brake systems of all of my cars. In fact, the only time I've ever had to replace brake components with lower milage was becasue the vehicel had been allowed to sit for an exteneded period of time or the vehicle received little use. Exapmples are a 93 Buick that was my grandmother's car until she passed away in 1998. I got it in 2000 with something like 23,000 miles on it. A number of the rubber components on the car were failing from non-use. Brake components included. I also had to replace the front brake caliper on a 1979 BMW R65 motorcycle with 22K miles. It had been sitting disassembled for 15 years. The MC was frozen up. I managed to pop loose the junk that was plugging the holes in it and it has worked fine ever since. Still using it. Now I did flush that little bitty brake systome but I almost had to just to bleed it.

Brake lines are more apt to corrode from exterior corrosion.

Just to make the point that I too hold onto vehicles for wuiate a while, I have a 96 Ford Explorer with 170K miles that I've owned since 1997, a 2003 Ford Superduty with 115K miles. I have no plans to get rid of either anytime soon.

Al that siad, if you want to flush the system, it won't hurt anything. I would recommend changing other fluids on a regular bsis however (oil, coolant, tranny fluid)
 

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I keep my cars forever too. My Tercel is 18 years old this year and the Camry 13 years old. I have to admit though, that I have never flushed the brake fluid on either of them. I didn't realize DOT 3 is hygroscopic. What happens if moisture gets inside the brake system? The brake system is sealed, so theoretically no moisture should get inside - yes?
This article pretty well sums it up: http://www.aa1car.com/library/bfluid.htm
 

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I guess I'm a bit hyper sensitive to the problem of lowered boiling points of aging brake fluid because of my 25 year old Jaguar. It uses inboard rear brakes...These rear calipers are right up against the diff and also the exhaust system. Which is to say they are exposed to higher temps than most braking sysems. The constant cycling of brake fluid temps [from highs to lows] creates an ideal condition for moisture to be accumulated. Nearly every one of these systems, when neglected, has milky white stuff mixed in the fluid when drained or opened up for service.

Which reminds me....I'm overdue for a refresh. sheesh.
 

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I see you are very concern about the old fluid, you are correct, but more important (I think) is that he did not lube anything. The caliper pins (bolts) should always be lubed and the caliper surfaces that the pads ride on...
 

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I see you are very concern about the old fluid, you are correct, but more important (I think) is that he did not lube anything. The caliper pins (bolts) should always be lubed and the caliper surfaces that the pads ride on...

I'm afraid I have to disagree. The surfaces of the pins should be clean and shiney ie not scuffed and/or their coating worn down. Reason for no lube is....it attracts and collects brake dust - which by nature is highly abrasive and can actually hinder the free movement of the pads - thus contributing to their early demise.

It really depends on the point of view I guess. A shop might want to do this to get their customer back in there sooner - grease 'em up!!. But the DIY guy doesn't want to have to do this job any more than necessary....so it's cleanliness for him. :-D
 

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TMack - thanks for posting the article on the brake fluid. Interesting read. The potential problem with water in the brake fluid is a risk of boiling the brake fluid and causing a spongy brakes due to vapour lock. I will pay more attention to this now.

As far as lubricating the slider pins is concerned, do you mean to say that you leave your slider pins completely dry? If they are dry, don't you have problems with the pins rusting and seizing the calipers? Before my Camry, I had a '91 Buick Regal with all four disk brakes. If I did not lubricate the sliders every 6 months, without fail, they would seize up solid within a year, resulting in a rather expensive repair. Your thoughts please?
 

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TMack - thanks for posting the article on the brake fluid. Interesting read. The potential problem with water in the brake fluid is a risk of boiling the brake fluid and causing a spongy brakes due to vapour lock. I will pay more attention to this now.

As far as lubricating the slider pins is concerned, do you mean to say that you leave your slider pins completely dry? If they are dry, don't you have problems with the pins rusting and seizing the calipers? Before my Camry, I had a '91 Buick Regal with all four disk brakes. If I did not lubricate the sliders every 6 months, without fail, they would seize up solid within a year, resulting in a rather expensive repair. Your thoughts please?
If pins are rusting, they need replacing. But what made them get so hot in the first place??? (I can't imagine having to tend to that kind of "regular" maintenance on a six month basis!!). They should have a coating that prevents rust. Let me ask you - did you use OEM parts (pads, pins, rotors)? Did the dealership do your brake work?? I am fanatical about OEM parts and dealer workmanship. Esp on my Asian cars. I always take my car to the dealership for work I can't DIY. which is really just timing belts at this point on my Avalon (1996). Sorry to say I don't have any experience with GM in a long while....what did the shop manual recommend?
 

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Sheesh. Lot's of chatter on the web about lubing pins.... nothing official, just lot's of opinions. I dunno.

If you really feel the need to lube them use a quick drying spray-on graphite lube. LubriPlate brand comes to mind (as manufacturer). You wont find it at PepBoys ;-) Yet, I don't know the heat tolerance, now that I think about it.

Some say white lithium grease. Sheesh. that fine for door latches but has no tolerance for heat.
Some are saying WD40. OMG! that's not a lubricant. It's properties mostly resemble kerosene.
Some say silicone - it wont stay in one place. Ditto synthetics.
They are all over the map..... maybe I'll dig up my 'yota Svc ROM and see what it says...Sheesh. What a can of worms I've opened!!! :rolleyes:
 

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Ok. Reference page 27 of the brake system shop manual.
The shop manual says to coat the moving parts and the inside of the dust boot with Lithium Soap Base Glycol Grease. I have no ideas on where to buy that??? excepting the dealer. and I'm betting they are going to look at you funny at the parts counter when you roll that off the tongue!

(I learned something! Thank you.)

I'll check Google for source.
 
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