bleeding rear brakes
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That did the trick - and again moved my problems downstream.
No leak when pumping the brakes from the bango now, but I do have fluid leaking out of the back of the caliper where the piston pokes through(the parking brake is off currently)
I think I remember getting an o-ring in the kit that I didn't use, so hopefully that is what I need to seal that up. the peddle feel is great, but the brake pad doesn't move, nor the caliper piston - assuming since it's leaking.
I did bleed the fronts while I had everything out, so they are rock hard now - and the nasty fluid is gone.
And a question for those that are familiar with a properly working rear caliper. The support bracket - it has one solid bracket bolt on one end, and then the other slide pin. I lubed it, but is there anything else for it? they seem very loose/sloppy in the holes. I know they need to have in and out room, but I can rock the bracket about a half inch from side to side when it's attached. It looks like then the pads clamp down a little tighter/piston compresses that it will take up some of this slop, but still seems pretty loose to me.
No leak when pumping the brakes from the bango now, but I do have fluid leaking out of the back of the caliper where the piston pokes through(the parking brake is off currently)
I think I remember getting an o-ring in the kit that I didn't use, so hopefully that is what I need to seal that up. the peddle feel is great, but the brake pad doesn't move, nor the caliper piston - assuming since it's leaking.
I did bleed the fronts while I had everything out, so they are rock hard now - and the nasty fluid is gone.
And a question for those that are familiar with a properly working rear caliper. The support bracket - it has one solid bracket bolt on one end, and then the other slide pin. I lubed it, but is there anything else for it? they seem very loose/sloppy in the holes. I know they need to have in and out room, but I can rock the bracket about a half inch from side to side when it's attached. It looks like then the pads clamp down a little tighter/piston compresses that it will take up some of this slop, but still seems pretty loose to me.
pulled the caliper apart and sure enough the rear parking brake O-ring was missing. Anyone have a trick for putting the new one in? spent 30 minutes wrestling with it trying to get that little sucker in.
the caliper piston - shouldn't be able to move by hand, right? book talks about using brake pressure or air pressure to pop it out - so wanted to confirm that it's a pretty darn tight fit.
as for the slop in the mounting bracket - one of the boots on the mounting bolt had slipped so that allowed a little play. The other side is still sloppy though - I put one wrap of duct tape on the pin. seemed to take up a bit of the slack, but still allows it to slide. we'll see if that holds up.
Thanks
the caliper piston - shouldn't be able to move by hand, right? book talks about using brake pressure or air pressure to pop it out - so wanted to confirm that it's a pretty darn tight fit.
as for the slop in the mounting bracket - one of the boots on the mounting bolt had slipped so that allowed a little play. The other side is still sloppy though - I put one wrap of duct tape on the pin. seemed to take up a bit of the slack, but still allows it to slide. we'll see if that holds up.
Thanks
DeadLastRacing
Well-Known Member
G damn man, I've never heard of someone having so many problems with a simple rear caliper!
91warrior
Well-Known Member
haha yea this system sure is being a pain for you. sounds like your having patience with it than i ever would.
as for the caliper piston, you should be able to push it in by hand as long as the bleeder is open. but it will take shop air to blow it out, really no other way to get it out of the caliper. again make sure you put a lot of rags between the piston and the outside of the caliper before you put air to it, so when it comes out the piston doesnt get damaged. also dont apply a lot of air. just little burst just so it pops out.
as for the caliper piston, you should be able to push it in by hand as long as the bleeder is open. but it will take shop air to blow it out, really no other way to get it out of the caliper. again make sure you put a lot of rags between the piston and the outside of the caliper before you put air to it, so when it comes out the piston doesnt get damaged. also dont apply a lot of air. just little burst just so it pops out.
Well I guess that's what I get for picking up a used unit instead of a new one - but still into it for less than half the price of new - and getting a learning experience out of it. I just have no reference for a properly working system, so that is a disadvantage. Makes it easier to be patient when you can still ride with no rear brake 
Sounds like my piston is little too tight then, I can't budge it by hand. I will replace the two seals inside the bore too and see if that helps. I tapped the back to get it moving and then used air to pop it out.
Thanks all
Sounds like my piston is little too tight then, I can't budge it by hand. I will replace the two seals inside the bore too and see if that helps. I tapped the back to get it moving and then used air to pop it out.
Thanks all
DeadLastRacing
Well-Known Member
Can't move my piston by hand either, that a good thing. I use a small c-clamp when I have to change out pads to push the piston back into the housing.
91warrior
Well-Known Member
ok yea im sorry i am wrong. that piston might not move. i had compared it to my truck calipers when i had them off the truck and i could push it in with my bare hands. my bad for the false information.
as for the amount of play, im really not sure because i was working with a brand new caliper when i did my rear system and the it did have some play but really cant describe how much.
as for the amount of play, im really not sure because i was working with a brand new caliper when i did my rear system and the it did have some play but really cant describe how much.
I got the parking brake O-ring to seat in it's groove last night. let it sit with a little weight on it over night just to make sure it was happily in there. relubed it today, and put in the new seals in the bore. lubed the piston and stuck it back in. checked that the O-ring was still in place and buttoned everything else back up.
the piston moved back and forth more easily now, so I thought that was good.
I think most of my mounting bracket slop was due to the dust boots for the slide pins not being 'tucked' into the slide bores. I was only able to get it squeezed in about 3/4 of the way around, but that seemed to take up the slack. put the caliper on and bled it out no issues. stepped on the brake to test it - fluid steaming out of the rear where the piston pokes out. not looking forward to taking it apart again, but not sure what else to do at this point. it has all new seals so it shouldn't leak.
any ideas - other than buying a brand spanking new one?
Thanks
the piston moved back and forth more easily now, so I thought that was good.
I think most of my mounting bracket slop was due to the dust boots for the slide pins not being 'tucked' into the slide bores. I was only able to get it squeezed in about 3/4 of the way around, but that seemed to take up the slack. put the caliper on and bled it out no issues. stepped on the brake to test it - fluid steaming out of the rear where the piston pokes out. not looking forward to taking it apart again, but not sure what else to do at this point. it has all new seals so it shouldn't leak.
any ideas - other than buying a brand spanking new one?
Thanks
91warrior
Well-Known Member
that sucks. this thing is refusing to work for you. i cant give any advice for i never rebuilt one of these calipers. ill have to look in the manual for the caliper so see how everything is organized in there. hate to see you give up on this when you went this far with it. hope things start to turn around for you. let us know if you find anything out.
Pulled the caliper apart again and found the o-ring was trashed, looks like it probably happened when I was putting the piston back in there, nicked it and tore it. hoping I can find the o-ring and not the whole kit again.
DeadLastRacing
Well-Known Member
it it the small o-ring? YOu can get them at any harwere store. I had one go bad and a quick run to lowes got me back in business. I ordered a seal kit for the caliper too, still have it in its original packing, want it? Pay what I paid and its yours.
cool, I was hoping between HD, Lowes and Autozone that I would be able to find one that matches. I just replaced the two big seals - and thankfully didn't destroy them in this process
If I do though I will let you know - my quick ebay check today didn't turn up the kit that I had bought before for the rebuild.
had to pick up more brake fluid too - I went through a quart with this process - but I did flush/bleed the fronts too.
If I do though I will let you know - my quick ebay check today didn't turn up the kit that I had bought before for the rebuild.
had to pick up more brake fluid too - I went through a quart with this process - but I did flush/bleed the fronts too.
Success! swung by Harbor Freight this morning and picked up their 250 pack of Orings for $4. It has probably 20 that look like the one that I trashed. wrestled one in(gotta be a trick to these) but gouged it pretty good putting the piston in. got another one and was able to get it seated.
put the caliper back together and on. I was a little worried since I seemed to have pushed that green seal through a little while putting the piston in. put it on anyway and bled it out and stepped on the brake. fluid leaked, checked it closer and saw it was the banjo again so used the lighter trick and cranked it down again - tested again, got one little seep but then seemed to seal and I could see the piston moving in and out. tossed the parking brake cover on(no block-off plate yet) and took it for a quick spin. brakes worked, I just have to get used to having them again - sure makes it easier going down hill and around corners. did a few hard stops and it locked up the rear fine so that have plenty of grab.
Thanks for all the help!
put the caliper back together and on. I was a little worried since I seemed to have pushed that green seal through a little while putting the piston in. put it on anyway and bled it out and stepped on the brake. fluid leaked, checked it closer and saw it was the banjo again so used the lighter trick and cranked it down again - tested again, got one little seep but then seemed to seal and I could see the piston moving in and out. tossed the parking brake cover on(no block-off plate yet) and took it for a quick spin. brakes worked, I just have to get used to having them again - sure makes it easier going down hill and around corners. did a few hard stops and it locked up the rear fine so that have plenty of grab.
Thanks for all the help!
missouritrailrider
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damn man bout time lol
91warrior
Well-Known Member
haha thats awesome! after all that trouble you have them. i will admit i had all new parts except had to rebuild the master cylinder (i had gotten a brand new caliper for christmas) so mine went together great. but that is great to hear
Yeah, I'm happy to have that taken care of. That was the last big thing for getting it operational. Still need to tweak the carb a little I think, and rear axle bearings - but other than that, at least I can get out and enjoy it more easily now.
