I recently bought some ebay aftermarket calipers and after taking out the caliper inlet plug it looks like the fluid sat so long or had a ton of debris in it. It actually looks like brown sugar. I'm planning on taking the plugs out flushing it on the work bench. Should I just use cheapo brake fluid and flush that way or is there a commerical cleaner that would work and be safe to use? I was thinking maybe engine degreaser or brake cleaner? I've never ran it through the insides of calipers before so I figured I should ask first.

 

Denatured alcohol, nothing else. Can be purchased at hardware stores along with big box stores.

Denatured alcohol, that is what you want for brake parts. Anything else can contaminate the system and cause issues such as swelled seals (system locks up), or degradation of seals (you drive into the back of the car in front of you).

RBob.

 

Whats your status on this after 2-3 weeks?

My
That "brown sugar" is rust powder from the caliper housing.
(The piston is either aluminum, or some other non-rusting material.)

RBob is correct about what to use, but don't expect flushing to get
the compacted material off internal surfaces. Additionally, calipers
are incredibly easy to service, with the only parts being the internal
o-ring, and dirt seal -- usually less than $5 bucks per kit at any
good parts supply. To get the piston out, I put a piece of wood in
the caliper for the piston to land against, and then apply air pressure
(with a rubber-tipped nozzle) to the brake line inlet.
(Keep your fingers out from between the piston & wood. )
After cleaning all components, and re-installing the o-ring, lube it
with some clean brake fluid. A C-clamp is useful for getting the piston
back in, which has to be pushed in straight. The previous wood
block works very well, with a big enough C-clamp (usually 4 -6").

Good luck.

 

Cleaned it several times with denatured alcohol. Used a small pipe cleaner to fish around in the caliper inlet. I got all the packed debris out of the threads. I went as far as shaking it around with alcohol in it then letting it run out. I took out the fittings on each side of the caliper and back flushed them that way too. After about 1/2 of a can I got it so it looks clean and alcohol runs out clean. I rather not mess with taking it apart since it has 4 1.75" pistons on each caliper so would probably take me awhile messing with it. I plan on flushing out brake fluid too since it's been 8+ years since the last time I've changed out my fluid so I'm well overdue for that (car has been sitting for a long time) so that should help flush out any of debris floating around if there is any left.

I didn't like the caliper inlet fittings so I decided to cut new threads into them. I hate it when aftermarket companies think they have to change the threads to force the consumer to buy new lines, which they'll gladly sell to you at $60 for the front pair. I cut them to accept the OEM banjo bolts.