The only way to totaly get the calipar 100% clean is to pull it apart. No amount of bleeding will get all the crud out.
But, is it needed most times? NO.
If I buy a used car and know the brake fluid is Expresso colored its time to pull the piston (s) out and clean. This is when I spend the $100 bucks or so and get all new flex hoses too.
Case in point. My 78 LRT has been sitting dead for 15 years. I am building its 410 stroker now and when I get the truck in the shop I will be replacing the master cylinder to a 2 bolt, the vac booster, the rubber flex hoses and any of the steel lines as needed. I will be pulling the Calipers and wheel cylinders apart to clean and inspect them. Its easy work.
One of the first things I drilled into my sons head,
"If you add to the GO you have to add to the WHOA" .
Retired, US ARMY 1973-1994
ASE mechanic, Electrical 1994-1997
Retired GTE/VERIZON/FRONTIER 1997-2015
Posting cheap tech help (CRAP) here since Nov 97, 1000's of posts, some may be good.
03 Suzuki Burgman 650(Burger King) Scooter
65 Formula S Cuda
78 Little Red Express Truck
98 Buick Regal (wifes car)
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