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JRust
Okay so I haven't been able to drive my car for the last month from overheating issues. I finally got my new renegade radiator installed & solved my cooling issues. Once I am thru with the whole burping process I want to go for a drive. I back up in the driveway to turn around & my foot goes to the floor when I use my brake. I pump the pedal but get nothing. I push the car back in the garage. Pop my hood & check my fluid. Reservoir is bone dry WTF.gif

I pull my access plate below the rack. Everything in place confused24.gif . By the way I replaced this 19mm Master cylinder 3 months ago. It has maybe 500 miles on it tops. I get my bottle of brake fluid & proceed to fill my reservoir. Then peek under my car to see if there is a leak. Heck yeah it is leaking from my master cylinder. I did not have a leak before it was parked??? The fluid is coming from the top of the master cylinder where the feed tubes go into the rubber seals. It is leaking from outside the seals? Coming out very quick? What can I do to fix it? What would cause this? The only thing that has change is I welded in a new section in my front trunk. So there was some heat down there but not that close to the master cylinder. WTF.gif

What do you suggest?
davep
You don't have the straws properly inserted into the master cylinder most likely. There needs to be the washers instaled for the metal tips of the straw to seat on, and the rubber seals must not be cracked or dirty.
JRust
QUOTE(davep @ Oct 7 2008, 08:48 PM) *

You don't have the straws properly inserted into the master cylinder most likely. There needs to be the washers instaled for the metal tips of the straw to seat on, and the rubber seals must not be cracked or dirty.


They were fine for a good 2 months. Can the straws work their way out or do they normally? What is the best way to get them to seat properly?
scotty
I'd check to make sure the seals are in and the lines are properly in the seals.

Is it draining down the feed lines (on the outside) to the MC? Then I'd check to see if there's a hairline crack in one or both of the feed lines.

The reservoir has two separate sections for when it runs low... is it empty in both? Is that a possible failure mode?

I hated putting the lines into my MC last week. After 2 or 3 hours of trying, I went off for "a rest" and when I came back, "snick-snick!" in they went. Bah!
JRust
QUOTE(scotty @ Oct 7 2008, 09:00 PM) *

I'd check to make sure the seals are in and the lines are properly in the seals.

Is it draining down the feed lines (on the outside) to the MC? Then I'd check to see if there's a hairline crack in one or both of the feed lines.

The reservoir has two separate sections for when it runs low... is it empty in both? Is that a possible failure mode?


It isn't leaking down the straws & they seem to be in the seals fine. They are not leaking out the top of the seal next to the straw. They are leaking around the bottom of the seals like they are not in enough. Not sure if I can just push them further in or how too?
scotty
Hate to say it, but pop them out and try again...I hate that solution

I'm smart enough to know I'm out of ideas and not of much help. sorry
roadster fan
Hey Jamie,

I would have to say that at least one of the lines got bumped and popped out while working on the car. Seems strange since you said you had to remove the tray to get access to the MC.

Where did fluid go that was in there initially, you never saw a leak?

Only solution I see is to take the lines out and reinstall. I hate that job, did it twice in the last 4 months headbang.gif Make sure to check the rubber seals for cracks and dirt.

Jim
JRust
I did have some leaks under my car. I put some cardboard under it. I do have a tranny leak & just thought it was that. Guess not huh? I will get under there & try to reinstall them tommorow night. Any tips other than making sure no cracks or dirt?
Eric_Shea
You should get new seals for that job.

Again, make sure those metal washers are in there and get new rubber seals for the MC.

Beware... this almost ranks as the top PITA job on a 914. This and replacing the rear hard lines with the engine in.
computers4kids
QUOTE(Eric_Shea @ Oct 8 2008, 07:26 AM) *

this almost ranks as the top PITA job on a 914

agree.gif
On a watercooled car it's even more of a PITA! If you ran your lines like Renegade does there right there to add more fun to the job...just did that one a few months ago in the Summer heat sad.gif

JRust
Great! Now I can really look forward to it dry.gif . Guess I will spend my evening cussing in my garage. I do not remember there being any metal washers?
Isn't it just the rubber ones coming out of the master cylinder?
Where do the metal washers sit?
Eric_Shea
Metal washers go in first. Then the rubber seals.

The rubber seals "must" be seated properly or else they'll... ummmmm... LEAK! w00t.gif

(which may be your problem)

Do you want me to get some new seals for you? I owe ya one! LOL
shoguneagle
This article is excellent but it leaves a couple of questions for me. The questions involve the washers and the actual installation of the rubber seals. I do not remember any washers on the metal ends If these are needed could someone have pictures and also where to get them. I have found none listed at Pelican.

Also what is the correct installation of the rubber seals. Are they installed first in the master cylinder or on the lines before inserting the metal ends.

This is a completely unknown area to me and if not done right can cause some potential exposure to accidents.

I have bought a new master cylinder with the rubber seals already installed. The next thing: Where do I go from here????

Thanks,
Steve Hurt
Eric_Shea
QUOTE
I do not remember any washers on the metal ends


Not following you. Read the previous line:

QUOTE
Metal washers go in first. Then the rubber seals.


You should have washers under your grommets.

Some have theories on this. The best I've heard, and it may apply in your case of "building" a car vs. repairing a car, is this:

Bench build it with the short metal tubes installed and then hook it up to the reservoir lines that come down. This will circumvent a lot of issues like:

1. I can't get the rubber grommets in with the metal tubes in them.
2. I can't get the metal tubes to seat in the properly seated grommets.

All of which can be extremely difficult in the precarious position of being flat on your back under your car while developing neck muscles you didn't know you had or needed.

So, if possible, build it on your bench first as follows:

MC -> Washers -> Rubber Grommets (you'll know when they seat properly) -> Stubby Hard Lines.
shoguneagle
Thanks, Eric.

Once I got to looking at the new master cylinder, it made sense. I also have a rebuildable 19mm master cylinder which I believe the washers will be with the rebuild kit.

I just pushed in the reservoir lines to the grommets backs after the grommet installation.

I am putting all new lines, reservoir, clamps, master cylinder, etc. in my car.

Pelican does not offer the rebuild kit for the 19mm. Need souces where I can get the kit for the old M/C I have.

Thanks,
Steve Hurt
0396
QUOTE(Eric_Shea @ Oct 8 2008, 09:33 AM) *

Metal washers go in first. Then the rubber seals.

The rubber seals "must" be seated properly or else they'll... ummmmm... LEAK! w00t.gif

(which may be your problem)

Do you want me to get some new seals for you? I owe ya one! LOL



I don't ever remember replacing any 'metal' washers - I've replaced two M/S in my time and don't ever remenber using these washers...I must be lucky

But then... I an old fart ...mybe I just don't remember. The first time was in my 70 911 back in 75...
Eric_Shea
QUOTE
I've replaced two M/S in my time and don't ever remenber using these washers


901 355 936 00

Maybe they're only in M/C's not M/S's biggrin.gif
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