Cleaning caliper bore crud

JLamb

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Is there a consensus on the best solvent or technique to clean the crud in the caliper bores? Mine seems to have seen some moisture in the fluid.
 
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+1 on all the above. While we might strive for hospital clean, it is most important to have any crud removed where the seals seat. Brake fluid as a solvent is good, but naptha (lighter fluid) is OK as a slower acting solvent too, but wipe out the bores, etc. with isopropyl alcohol afterwards as it will clean up residual brake fluid/naptha/moisture and flash off. Polish the outer pistons, and if you must use an abrasive, use crocus cloth or a minimum 900 grit or higher. Some aluminum polishes or silverware polishes have a very mild and finer grit, you do not want to "sand" them. Microfiber cloths seem to me to remove stuff better than cotton rags. Clean off with naptha and alcohol. Lube all parts with brake fluid prior to re-assembly of the pistons.
 

ST1100Y

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A slight squirt of alloy wheel cleaner... spray on, let soak as advised (do not exceed the prescribed time), scrub with old toothbrush, nail-brush, dental pick, etc... rinse thoroughly with warm water, give it a second cycle if needed, rinse thoroughly, blow dry with compressed air, let sit to dry off for couple of hours and/or use heat-gun/oven (later if da wiffer permits ;-) ) for quick-dry...
I'm not a fan of using abrasives on calliper pistons... AFAIK are their coated... and if they show signs of pitting corrosion I replace them anyway...
 
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I would (and have used) use spray brake parts cleaner, since that's what the stuff is made for. Just be sure to keep it away from anything non-metallic (i.e. rubber, plastic,etc.). I'm assuming that since you're cleaning the caliper bores you've removed the old seals and will renew them when reassembling. Give the cleaner time to evaporate, then follow up with fresh brake fluid when reassembling as others have suggested.
 
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ST1100Y

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Not sure about anyone else, but I wouldn't use *anything* but brake fluid on the caliper internals.
Worked like a charm... really...
While refurbishing the, pretty neglected by PO, '94 ST I'd the problem how to clean the outside and the guts of them callipers, as all were totally dirty and seized up...

Sure, you have to rinse that out with water, which needs to be fully removed... the components must be sterile before continuing reassembly... brake assembly paste for installing rings and pistons...
But considering the MFG processes on the Nissin plant, them bits had already seen drilling/cooling oil for fabing the bores, grooves, connections, cutting threads, etc...
 

CruSTy

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The amount of mis-information that gets in these threads amazes me. READ THE LABELS!!! ACETONE is not brake cleaner. I have several different brands of brake cleaner on the shelf and none contain acetone. The active ingredient is tetrachloroethylene. I the old days it was carbon tetrachloride. Both are known carcinogens and clean brake parts, seals and rubber/neoprene parts included. They are meant to be sprayed on and evaporate very quickly. I would not soak rubber/neoprene parts in these for long periods of time. Definitely use clean new brake fluid for final cleaning and final assembly. NEVER use petroleum products for this unless you are working on a very old British braking system which is allergic to alcohol based fluids.
 

CruSTy

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Maybe you should tell these guys, they're under the impression it is.
I'm Busted. Showing my age. Never tried the Green stuff. Thank you for reading the label. BTW I would still not use acetone as brake cleaner just because someone can put it in a can and sell it.
 
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Thank you for reading the label.
Due to your post, I will read the labels from now on. It got me to looking for non-acetone brake fluid. So far, Auto-Zone is out. I'll check the other O'Reilly's and Napa next. If I can find it without acetone, the little green can will find its way out of my garage.
 

JPrieST

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Is there a consensus .....
Apparently not!:D

I use brake fluid and sometimes a plastic scratch pad like the ones sometimes found affixed to sponges. They are not likely to hurt the parts, and they do a pretty good job of cleaning the crud. Remember to rinse will with clean brake fluid afterwards.
 
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