shelbyz33 Posted April 16, 2015 Report Share Posted April 16, 2015 Figured I'd ask if anyone else has done this before I dive into it. Pulled the car out of the shed from winter had no brakes. Found the leak seeping out the bottom of the mater cylinder at the booster. Anyone know if it's an o-ring? Gasket? Easy? Hard? http://img.photobucket.com/albums/v648/shellbyzfan33/Mobile%20Uploads/20150414_165423.jpg Link to comment Share on other sites More sharing options...
importwarrior Posted April 16, 2015 Report Share Posted April 16, 2015 Rockauto.comHas them.Not bad but usually you need to simply replace the master cylinder.To me these cars seems that master cylinders go bad fairly often. Link to comment Share on other sites More sharing options...
delayed replay Posted April 16, 2015 Report Share Posted April 16, 2015 Yeah. That's my next project too. when I got my 89, I looked in the reservoir and it looked like mud caked in there. Don't know how hard it's gonna be to change out the master cfylinder, but definitely needs to be done. I may have to run new lines as well on mine. I feel your pain. Link to comment Share on other sites More sharing options...
scott87star Posted April 16, 2015 Report Share Posted April 16, 2015 Yep, its toast. You can rebuild but new reman ones are cheap. Link to comment Share on other sites More sharing options...
mikec Posted April 16, 2015 Report Share Posted April 16, 2015 It's more than just an o-ring or seal at the back of the master cylinder. As the others noted, a full master cylinder "rebuild" is needed: replacing the various rubber cups on the pistons at an absolute minimum. Rebuild kits typically are piston assemblies: pistons+cups already installed, fresh springs, etc. You swap out the guts of your existing master cylinder with the kits parts AFTER you completely clean the master cylinder bore, the fluid reservoirs, and the short rubber hoses connecting the reservoirs to the cylinder. In theory you also "hone" the master cylinder bore to make sure it's perfectly round and constant diameter with no scratches or other internal damage but few home mechanics have the tools to do this correctly. A remanufactured or new master cylinder is a quicker and easier repair especially for the typical DIY guy. Master cylinders typically fail because the brake fluid is contaminated. Fine silt/dust in the air gets caught in the brake fluid and acts like sandpaper to the little rubber cups, clobbering them. Brake fluid also absorbes moisture from the air; this moisture causes all sorts of problems: rust in the brake calipers, rust on the master cylinder piston parts, the water flashes to steam when the brakes get hot leading to loss of brake function (just like having air bubbles in the brake lines), and more wear-n-tear on the rubber piston cups inside the master cylinder. That's why maintenance manuals suggest replacing the brake fluid (and flushing the brake lines to get rid of the silt) every couple of years. You'll be amazed/disgusted at the crud and slime at the bottom of the brake fluid reservoir. The clutch system has the exact same issues too. mike c. Link to comment Share on other sites More sharing options...
shelbyz33 Posted April 16, 2015 Author Report Share Posted April 16, 2015 Wow, thanks for the responses guys. I'll buy a new one. Then basically when I start removing the old one things will become self explanatory for the DIY guy? Link to comment Share on other sites More sharing options...
importwarrior Posted April 16, 2015 Report Share Posted April 16, 2015 Yes it should.if possible flush out ALL the old fluid best you can. Link to comment Share on other sites More sharing options...
Starfighterpilot Posted April 16, 2015 Report Share Posted April 16, 2015 To me these cars seems that master cylinders go bad fairly often. Yeah your right. The brake master cylinder and clutch slave cylinders do go out fairly quickly unless you flush the brake and clutch hydraulic systems and clean out those systems fluid reserviors frequently. I was replacing 'em every 5 to 6 years until I made it a point to flush the systems and clean out the reserviors every Spring. Since I started doing that, about 12 years ago, I haven't had any weeps or leaks since. To me, it's worth the 1/2 to 3/4 of an hour it takes, once per year, to flush those hydraulic systems & clean the reseviors to save the bucks and labor of replacing those hydraulic cylinders. I would also recommend that you throughly clean ANY and ALL brake fluid off of the steering column coupling's INTERNALS immediately. WHY? Cuz brake fluid eats the crap out of the steering column's coupling rubber insert. You don't want to have to replace the entire coupling, cuz you've got 5 - 6 inches of slop in the steering wheel, cuz it's rubber insert has turned to mush. Been there gone thru that. For What It's Worth. KEN Link to comment Share on other sites More sharing options...
importwarrior Posted April 16, 2015 Report Share Posted April 16, 2015 not to mention that BC_99 is the only onethat sells a bolt in replacement coupler thatI know of.OEM is NLA Link to comment Share on other sites More sharing options...
hippynerd Posted April 16, 2015 Report Share Posted April 16, 2015 It seems like they only last about 25 years, then its common for them to leak.Its pretty easy to replace, and not too expensive ( I think I got one for under $50). Tip, unbolt the lines before unbolting the master, and clean that brake fluid with brake cleaner, get it all, that stuff is nasty and corrosive. Link to comment Share on other sites More sharing options...
shelbyz33 Posted April 17, 2015 Author Report Share Posted April 17, 2015 (edited) Ordered a new master cylinder today. Will be cleaning out all old fluid. And off topic, since it's so hard to find a cheap 83 hood and near where I live, anyone know where you can get the exact (weld or bolt on) hood scoop maybe? I have an extra stock hood that can be played with. Edited April 17, 2015 by shelbyz33 Link to comment Share on other sites More sharing options...
shelbyz33 Posted April 21, 2015 Author Report Share Posted April 21, 2015 This has nothing to do with the leak correct? http://img.photobucket.com/albums/v648/shellbyzfan33/Mobile%20Uploads/20150421_162858.jpg[/url] Link to comment Share on other sites More sharing options...
importwarrior Posted April 22, 2015 Report Share Posted April 22, 2015 the only thing with the pic above is that the fluid might possibly leak in to the booster.could hurt the inners of the booster. i had a much worse leak then that and i am finenow that i replaced the master cylinder. i did not change the booster. you should be good. clean it with brake cleaner. then clean prep the surface and prime and paint it. Link to comment Share on other sites More sharing options...
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