Jekyl and Hyde brakes

[madmax-im]

Update

OK been procrastinating this job for other BS...but now am getting back to finishing this project.Progress to date...Both front and rear master cylinders are off and di-assembled.Both spooge holes are clear...I have removed the rear brake caliper..and front ones will be coming off shortly.All brake lines fornt and rear are off too...
My question...I have noticed that the flat washer that sits under the ring clip on the rear MC...under the boot...is very rusty also when I removed the plunger and spring I was able to shine a lite in there and I see some dirt and debris on the inner walls ...so how do i get this crap out?Should I be soaking this in Brake Kleen?Is the washer important to be kept clean?
When I removed the rear caliper...I was able to push the piston in with my fingers does this mean its good?Most likely I will clean it up...once I figure out how to get into it...Ok lines are open ....Thanks

[Toolmaker Tim]

Crud on the walls

Madmax, I took a piece of gray scotchbrite and put it on a piece of dowel rod, soaked it in brake fluid and spun it around by hand while pushing and pulling it in and out. Turn your radio up with your favorite upbeat music if it helps! When every thing is clean, rinse well with brake cleaner to get any fibers or grit out. You just want to get the crud off, not change any diminsions. Now that I think about it a stiff bottle brush might do the trick also without any risk to the bore of the M.C. Since you got teh washer out you might as well clean it up. I used a wire wheel for that. Your caliper sounds like it is good. I used a bike pump to push the piston out. Put a piece of plywood in front of the piston so you don't shoot it through something that matters.

[Toolmaker Tim]

Oops!

Before you take the bike pump to the piston, remove the rubber boot. No sense ripping up something that still good. I understand some guys use a grease gun to push the piston out. Sounds messy.

[madmax-im]

Re: Oops!

Originally posted by Toolmaker Tim
Before you take the bike pump to the piston, remove the rubber boot. No sense ripping up something that still good. I understand some guys use a grease gun to push the piston out. Sounds messy.

Hmmm...I am puzzled...Why do i need to push the piston out?Is that how I clean it?I thought that th caliper could be dis-assembled?I think I'm going back to reread some threads...

[Ken Talbot]

You need to remove the piston from the caliper to get at the last bits that need to be removed/cleaned/replaced. Sometimes you can remove it with a pair of slip-joint pliers.

If it is stuck, that's where the grease or compressed air come in. The compressed air technique is actually a bit spectacular, and more than a bit dangerous. When it goes, it goes with a he!! of a bang and the piston comes out at an amazing speed. Stuff lots of rags between the piston and the other side of the caliper, and keep your fingers well away.
BTDT

[madmax-im]

Originally posted by Ken Talbot
You need to remove the piston from the caliper to get at the last bits that need to be removed/cleaned/replaced. Sometimes you can remove it with a pair of slip-joint pliers.

If it is stuck, that's where the grease or compressed air come in. The compressed air technique is actually a bit spectacular, and more than a bit dangerous. When it goes, it goes with a he!! of a bang and the piston comes out at an amazing speed. Stuff lots of rags between the piston and the other side of the caliper, and keep your fingers well away.
BTDT

Ken...so far i am just doing the rear caliper...when i removed it off the brake rotor I was able tp push the piston in with my thumb...it moved freely...so now its sitting in the caliper down far enough that apair of slip joint pliers wont work....I'm gonna try a bicycle pump 1st as i dont have anything else...Thanks.I've been away from this too long and need some refresher...going to do some more reading before going any further....

[madmax-im]

How many PSI?

OK included is one pic of the piston pushed out with abt 15-20 psi...from a small compressor that is old.So based on how far it went do you think 100PSI will move it?My brother is going to take the caliper to work where he has a good compressor...I told him to be aware that it will "POP"if it is stuck...if not it will just come out without any drama...is this correct?Notice in the pic how much crud there is on the piston...the rubber boot has a small tear in it...so it prolly has to go...

[Ken Talbot]

Re: How many PSI?

Originally posted by madmax-im
I told him to be aware that it will "POP"if it is stuck...if not it will just come out without any drama

Oh yeah, 100 psi will move it!

Let me rephrase - if you use compressed air to remove a piston, there WILL be drama. It won't just pop, it will come out with explosive force. That's why you keep your fingers WELL away, and stuff LOTS of rags in there to soften the blow to the other side of the caliper. Be prepared to have anybody within earshot looking over your way to see what the %$@# just happened!!

[madmax-im]

its out

just got a call from my bro' at work and he was able to get the piston out with 100 PSI...he said it came out easily and all is well.So later today I'll be cleaning it up.I am encouraged that it was not stuck and a good cleanup will prolly do the trick.From what I can see the sticky brakes would appear to be coming from the fronts...getting closer to the goal..Thanks for all the help...

[Toolmaker Tim]

Cleaning the caliper

When you clean the caliper, make sure you take out the seal ring inside the caliper bore. Use something blunt or soft to take it out. A somewhat flexable piece of plastic comes to mind. I whittled down a popsicle stick. Make sure you clean all the gunk out of the groove the seal fits in. The gunk gets behind the seal and makes things tight. Between the gunk and the little black floaters in the fluid, the reason for a good cleaning becomes apparent very quickly. All the brown and tan nasties have to go or you will be doing the job over soon.