MC piston stuck - now filling w/fluid

  • godsjester71
  • Topic Author
  • Offline
  • User
More
05 Sep 2006 07:39 #74613 by godsjester71
MC piston stuck - now filling w/fluid was created by godsjester71
The piston on both my ZX550 master cylinders are both stuck in the full in position, probably from sludge. It's soaking in brake cleaner right now.

I hooked up a caliper directly too it and filled the lines with brake cleaner, and tried to activate it by pulling and pushing in the caliper piston, no action. Probably due to viscosity. I was thinking of trying it with brake fluid next.

Does any one know a good trick to free it?

Post edited by: godsjester71, at: 2006/09/19 09:48

Please Log in or Create an account to join the conversation.

More
05 Sep 2006 16:27 #74703 by Mikes82KZ1100
Replied by Mikes82KZ1100 on topic MC piston stuck
My advice is to replace them. I don't mess around with brakes. REMEMBER..... If it don't run,NO problem. If it don't stop, BIG PROBLEM ! At a MINIMUM I would take them apart and inspect the bores,seals and pistons for problems. Cathy the cage driver is way more concerned about her cell phone and make up. You NEED brakes.:ohmy:

Please Log in or Create an account to join the conversation.

More
05 Sep 2006 16:49 #74709 by vegasjetskier
Replied by vegasjetskier on topic MC piston stuck
The viscosity shouldn't matter. The force is multiplied by the master cylinder, so you will need a lot of force to push it back with the caliper piston. Can you get a clamp on the caliper and push the piston in with it? Or bolt the caliper back on the fork and use a prybar to exert force against the piston. Be careful that you don't mar any of the metal surfaces.

godsjester71 wrote:

The piston on both my ZX550 master cylinders are both stuck in the full in position, probably from sludge. It's soaking in brake cleaner right now.

I hooked up a caliper directly too it and filled the lines with brake cleaner, and tried to activate it by pulling and pushing in the caliper piston, no action. Probably due to viscosity. I was thinking of trying it with brake fluid next.

Does any one know a good trick to free it?

Please Log in or Create an account to join the conversation.

More
05 Sep 2006 16:58 #74713 by vegasjetskier
Replied by vegasjetskier on topic MC piston stuck
If you have an air compressor, you can also try compressed air to push the piston out. Put a rag over the other end of the cylinder to catch any parts that might be forced out, then apply air pressure to the brake-line end of the cylinder using a trigger-operated valve. Wear safety goggles and make sure you do not have the rag-end of the cylinder pointed at your face!

Please Log in or Create an account to join the conversation.

  • godsjester71
  • Topic Author
  • Offline
  • User
More
06 Sep 2006 08:48 #74833 by godsjester71
Replied by godsjester71 on topic MC piston stuck
OK, after talking around a bit, I'm borrowing one from a friend till winter, it's off a 96 Katana. This way I still have a fighting chance of having the bike sorted out enough to go on our Two Weeks After Labor Day ride to SW Wisconsin.

So word has it that chances are the cylinder could be scored, rendering the unit useless. I am going to take it apart to see, but most likely I will be buying an aftermarket later this year.

Please Log in or Create an account to join the conversation.

More
12 Sep 2006 14:43 #76168 by kawaduce
Replied by kawaduce on topic MC piston stuck
How to dismantle... A safe but rather messy way is to attach a grease pump (this is tricky, since my native tounge is Swedish... Grease pump is, I hope, a manual device for pressuring grease into things. Popular tool for tractor owners...) and let it do the work. The pros are that the piston won't shoot out and that it always work, since grease has high density. The cons... well, basically, it's greasy and takes some time to clean it up.

Or you just stick with the borrowed M/C...

KZ1100B2 1982 - carb converted

Please Log in or Create an account to join the conversation.

More
12 Sep 2006 17:25 #76200 by steell
Replied by steell on topic MC piston stuck
Also known as grease gun locally :)

KD9JUR

Please Log in or Create an account to join the conversation.

  • godsjester71
  • Topic Author
  • Offline
  • User
More
13 Sep 2006 12:28 #76471 by godsjester71
Replied by godsjester71 on topic MC piston stuck
Actually went the lazy route:

eBay of course

Should be here in time for Rockerbox.

Post edited by: steell, at: 2006/09/19 18:16

Please Log in or Create an account to join the conversation.

  • godsjester71
  • Topic Author
  • Offline
  • User
More
19 Sep 2006 06:44 #77783 by godsjester71
Replied by godsjester71 on topic MC piston stuck
OK, my brakes are going back together tomorrow on the ZX550, and i have to fill 4 different paths (anti--dive till I can get the pregressive springs this winter.

Are there any helpfull tricks to make my life easier or make sure they fill right?

One person told me to attach a hose to the bleeder and run the tube into a container of brake fluid, so it doesnt suck air back in somehow. Unreliable source tho.

Ive also been told to make sure the MC is ALWAYS full, that one makes sense.

Please Log in or Create an account to join the conversation.

More
19 Sep 2006 06:58 #77785 by mariozappa
Replied by mariozappa on topic MC piston stuck
Yes you can put the hose from the bleeder into a bottle with some fluid and it will work.

After reading this thread, I did what JMKZHI suggested and it has seemed to work best for me so far.

Excellent thread here

Post edited by: steell, at: 2006/09/19 18:17

1977 KZ650C1
and the KZ650/KZ750 Conversion ;)

Please Log in or Create an account to join the conversation.

  • wireman
  • Visitor
19 Sep 2006 09:10 #77813 by wireman
Replied by wireman on topic MC piston stuck - now filling w/fluid
godsjester71 wrote:

The piston on both my ZX550 master cylinders are both stuck in the full in position, probably from sludge. It's soaking in brake cleaner right now.

I hooked up a caliper directly too it and filled the lines with brake cleaner, and tried to activate it by pulling and pushing in the caliper piston, no action. Probably due to viscosity. I was thinking of trying it with brake fluid next.

Does any one know a good trick to free it?<br><br>Post edited by: godsjester71, at: 2006/09/19 09:48

carefull with that brakeclean,it does terrible things to rubber parts !

Please Log in or Create an account to join the conversation.

  • godsjester71
  • Topic Author
  • Offline
  • User
More
19 Sep 2006 09:21 #77817 by godsjester71
Replied by godsjester71 on topic MC piston stuck
Are you guys doing this with just one caliper? With four, i can see this being a royal PIA, bubbles (crud in the case of the anti dive) flowing thru the top lines each time.

Please Log in or Create an account to join the conversation.

Powered by Kunena Forum