No Brakes - how hard to replace master cylinder plus lines?, looking for some guidance before I dig into my manuals... Options

[potomacmidget]

Merry Christmas everyone,

So, my brakes have been really soft, and I figured they were due a bleeding so I bought a pressure bleeder (watched Ian Karr video) and put my car on jackstands and removed all the wheels. Topped off the reservoir with fluid, then when I inspected the master cylinder and observed it was visibly "wet" with what I could only suspect was fresh fluid. First thought was "ok, not good, that must be my pedal problem" then I reached in there with an open end wrench to see if I could snug the connection, and the tubing (vertical) was not even connected to the MC, it just swung away when I touched it, then all the fluid poured out. I guess the threaded part of the tubing rotted away in the MC?

Regardless - looks like I need a new MC, and will have to inspect/replace sketchy lines, etc., and all that comes with that project.

Prior to diving into my collection of service manuals, any guidance on the challenges of this job? Do's and Dont's? It looks a bit nightmarish to access the MC, and since my simple job turned a lot harder, I will wait until my garage is warmer than 30F. All advice appreciated...

thanks,
Reg

[technicalninja]

It sounds like the feed tubes came out of the master.
There is pair of grommets that can rot and are difficult to install the metal lines in.
These can also be damaged by poor installation.

https://pmbperformance.com/products/master-...porsche-911-912

Below the grommets inside where their recess is a steel "stop" washer. These are critical to not lose and re-install below the grommets. There is a chance yours could be missing.

The original master was 17mm, parts are NLA.

What replaces it is an early 911 master. 1974 works for look up.

https://pmbperformance.com/products/19mm-at...che-914-4-914-6

Which can be had "clone" brand URO 9113550120 for less than $100. Rock Auto was $80.

There used to be "kits" to make the first 6" of steel line remote from the main tubes to ease installation. I couldn't find one.

Getting the tubes into the grommets is the bitchy thing here. After you do it once you'll get better. That first time can be (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif)

Pulling the gas tank will help and probably needs to be done for afore mentioned PMs.

If the master is fresh (less than 5 years old) it might be someone screwed up on the line install and you MIGHT just need the grommets.

If the system is OLD (more than 20) then you and PMB are going to become friends as ANYTHING made from rubber should be replaced. These include master cylinder, rubber lines, calipers/caliper kits, and the rear pressure valve.