I am loosing brake fluid very slowly, and the area where the Mcylinder bolts onto the booster is a little damp. Also I have bled the brakes from furthest wheel away to nearest and even bled at Mcylinder and I still have mushy brakes or a spongey feel. Would it be safe to say that both problems are due to the Mclyinder and that I need to replace or rebuild it? Has anyone rebuilt one, and how hard was it? Courtesy Nissan wants $180.42 for the MCylinder! All suggestions appreciated.
Thanks,
Steve

 

First of all Im asuming you dont have ABS. Second if your losing fluid then you need to isolate the area thats leaking and fix it (obviously). If the leak is in the master cylinder side then replacing would be preferred but if you short on money it is possible to rebuild. However! If you dont know what your doing then dont try it, especially the brakes! The master cylinder isnt too complicated but without the proper knowledge you could seriously mess up you your car and anyone who doesnt jump out of your way in time.

 

Fix it! This same problem happened on my '89. Over one week of not driving the car, all the fluid leaked out. A rebuilt master cylinder from Autozone only cost me about $55 (plus core charge), and replacing it was very easy in terms of removal and installation (two bolts to vacuum booster, then the four flared nuts for the brake lines). Make sure you bench-bleed the master cylinder first; the master cylinder should come with the necessary kits and instructions on how to bench-bleed the master cylinder.

 

[QUOTE]Originally posted by Sparhawk


Fix it! This same problem happened on my '89. Over one week of not driving the car, all the fluid leaked out. A rebuilt master cylinder from Autozone only cost me about $55 (plus core charge), and replacing it was very easy in terms of removal and installation (two bolts to vacuum booster, then the four flared nuts for the brake lines). Make sure you bench-bleed the master cylinder first; the master cylinder should come with the necessary kits and instructions on how to bench-bleed the master cylinder. [/QUOTE

Autozone you say?

 

Acutally I do have ABS. The rebuild instructions in the Haynes and Chilton manuals looks pretty straight forward, but for $55 a rebuilt one from autozone catches my interest. Thanks,
Steve

 

call around and see what you can get a reman part for. should be around $50-60. they're not had to change out, and if you know how to properly bleed your brakes, you're 90% there. just be sure to hose the whole engine bay down afterwards to remove any stray brake fluid... if it sits on your paint very long, it'll dissolve it.

 

Thanks for the help!
Steve

 

Yeah, I definitely know about the dissolved paint part ... the master cylinder on my '89 had a small leak which I didn't pay much attention to until all the paint near that area on the firewall started peeling and flaking away. Only after I lost all the brake fluid within a matter of a week did I finally look into getting a new master cylinder, which excluding the bench bleeding part (doable, but big mess ...) was an easy swap.

Anyway, prices are as follows for an '89:
* Kragen/Shucks/Checker (remanufacturer: A1 Cardone)
$57.99 GXE w/o ABS
$69.99 SE w/o ABS
$73.99 all w/ABS
All with $50 core charge; all with lifetime warranty.

* Autozone (remanufacturer: Fenco)
$54.99 GXE w/o ABS
$54.99 SE w/o ABS (what I have)
$68.99 all w/ABS
All with $50 core charge; all with lifetime warranty.

You can purchase a new unit through Autozone's website for $76.99 with the reservoir, made by Fenco, or a new one from Beck Arnley for $209.99 (which puts you in the dealer range). Kragen has the Beck Arnley for $183.99.

Feel free to check out Autozone (http://www.autozone.com/) or Kragen/Shuck/Checker (http://www.partsamerica.com/) for more info or if you want to do your own research on the cost between a remanufactured unit vs. buying a kit to do it yourself.

Good luck! -Alan

 

Thanks for the help Alan, I went with the 76.oo autozone one, should be here tuesday. I am thinking about trying to bleed or prime it while on vehicle. Have you ever done that?
Thanks,
Steve

 

Steve,

When I bench bled the master cylinder, I had the unit mounted in a vise grip, and I followed the enclosed instructions on how to bleed the master cylinder. I think it's doable to have the master cylinder mounted first, but to do it may mean you may need to have two people to do the actual operation (one to pump the brake pedal, one to watch the brake fluid coming out for air). The kit should come with two or three plastic plugs and one plug with a male nipple on it, which you hook a clear plastic tube to it.

Now, the way I did it with the master cylinder mounted in a vise grip and the reservoir filled with brake fluid, I took a philips screwdriver and pumped the master cylinder. Three of the four ports should be plugged with the enclosed plastic threaded plugs. The fourth one with the male nipple fitting and the plastic hose should be routed back to the master cylinder reservoir because it will have brake fluid (and air) coming out of it, and you can reuse that brake fluid. Keep pumping the master cylinder with the philips screwdriver until all air is cleared out of that line. Then remove that plastic nipple and swap it with one of the plugs. Repeat procedure for all four ports on the master cylinder.

Now, if you were to do it with the thing mounted in your car, you'd follow the same procedure except someone will have to pump the brake pedal inside the car while you watch the plastic tube for air pockets.

It's not hard ... it's just messy because the plastic plugs that came with my master cylinder didn't thread in properly ... but it has to be done to ensure that the master cylinder is purged free of air before you hook your brake lines to it. Of course, once you hook those brake lines to it, you're going to need to bleed all four calipers since there's a very good chance that there'll be air in those lines as well from when they were disconnected from the master cylinder.